From 2cdfe5799e45e64ff5dab5aa35afa0ed9f6ae4e9 Mon Sep 17 00:00:00 2001 From: Matthias Seemann Date: Mon, 21 Oct 2013 23:17:21 +0200 Subject: [PATCH 1/3] - added delayed(fn, timeout) - a higher-order function which creates a delayed version of the given function - updated Lodash library --- index.html | 9 +- lodash.js | 10257 +++++++++++++++++++++++++++++++-------------------- main.js | 9 +- 3 files changed, 6274 insertions(+), 4001 deletions(-) diff --git a/index.html b/index.html index d10a89c..913eb66 100644 --- a/index.html +++ b/index.html @@ -91,6 +91,12 @@ + @@ -108,6 +114,7 @@

Mousemove Events:

+

Delayed Mousemove Events: delayed(fn, 200);

Debounce Inmediate: _.debounce(fn, 200, true);

Debounce Inmediate: $.debounce(200, true, fn);

Debounce: _.debounce(fn, 200);

@@ -116,7 +123,7 @@

Throttle with trailing: _.throttle(fn, 200);

Throttle with trailing: $.throttle(200, false, fn);

Throttle: $.throttle(200, true, fn);

- + Fork me on GitHub diff --git a/lodash.js b/lodash.js index 9168e14..e48344d 100644 --- a/lodash.js +++ b/lodash.js @@ -1,93 +1,89 @@ -/*! - * Lo-Dash v0.7.0 - * Copyright 2012 John-David Dalton - * Based on Underscore.js 1.3.3, copyright 2009-2012 Jeremy Ashkenas, DocumentCloud Inc. - * +/** + * @license + * Lo-Dash 2.2.1 (Custom Build) + * Build: `lodash -o ./dist/lodash.compat.js` + * Copyright 2012-2013 The Dojo Foundation + * Based on Underscore.js 1.5.2 + * Copyright 2009-2013 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors * Available under MIT license */ -;(function(window, undefined) { - 'use strict'; +;(function() { - /** - * Used to cache the last `_.templateSettings.evaluate` delimiter to avoid - * unnecessarily assigning `reEvaluateDelimiter` a new generated regexp. - * Assigned in `_.template`. - */ - var lastEvaluateDelimiter; - - /** - * Used to cache the last template `options.variable` to avoid unnecessarily - * assigning `reDoubleVariable` a new generated regexp. Assigned in `_.template`. - */ - var lastVariable; + /** Used as a safe reference for `undefined` in pre ES5 environments */ + var undefined; - /** - * Used to match potentially incorrect data object references, like `obj.obj`, - * in compiled templates. Assigned in `_.template`. - */ - var reDoubleVariable; + /** Used to pool arrays and objects used internally */ + var arrayPool = [], + objectPool = []; - /** - * Used to match "evaluate" delimiters, including internal delimiters, - * in template text. Assigned in `_.template`. - */ - var reEvaluateDelimiter; + /** Used to generate unique IDs */ + var idCounter = 0; - /** Detect free variable `exports` */ - var freeExports = typeof exports == 'object' && exports && - (typeof global == 'object' && global && global == global.global && (window = global), exports); + /** Used internally to indicate various things */ + var indicatorObject = {}; - /** Native prototype shortcuts */ - var ArrayProto = Array.prototype, - BoolProto = Boolean.prototype, - ObjectProto = Object.prototype, - NumberProto = Number.prototype, - StringProto = String.prototype; + /** Used to prefix keys to avoid issues with `__proto__` and properties on `Object.prototype` */ + var keyPrefix = +new Date + ''; - /** Used to generate unique IDs */ - var idCounter = 0; + /** Used as the size when optimizations are enabled for large arrays */ + var largeArraySize = 75; - /** Used by `cachedContains` as the default size when optimizations are enabled for large arrays */ - var largeArraySize = 30; + /** Used as the max size of the `arrayPool` and `objectPool` */ + var maxPoolSize = 40; - /** Used to restore the original `_` reference in `noConflict` */ - var oldDash = window._; + /** Used to detect and test whitespace */ + var whitespace = ( + // whitespace + ' \t\x0B\f\xA0\ufeff' + - /** Used to detect delimiter values that should be processed by `tokenizeEvaluate` */ - var reComplexDelimiter = /[-?+=!~*%&^<>|{(\/]|\[\D|\b(?:delete|in|instanceof|new|typeof|void)\b/; + // line terminators + '\n\r\u2028\u2029' + - /** Used to match HTML entities */ - var reEscapedHtml = /&(?:amp|lt|gt|quot|#x27);/g; + // unicode category "Zs" space separators + '\u1680\u180e\u2000\u2001\u2002\u2003\u2004\u2005\u2006\u2007\u2008\u2009\u200a\u202f\u205f\u3000' + ); /** Used to match empty string literals in compiled template source */ var reEmptyStringLeading = /\b__p \+= '';/g, reEmptyStringMiddle = /\b(__p \+=) '' \+/g, reEmptyStringTrailing = /(__e\(.*?\)|\b__t\)) \+\n'';/g; + /** + * Used to match ES6 template delimiters + * http://people.mozilla.org/~jorendorff/es6-draft.html#sec-7.8.6 + */ + var reEsTemplate = /\$\{([^\\}]*(?:\\.[^\\}]*)*)\}/g; + /** Used to match regexp flags from their coerced string values */ var reFlags = /\w*$/; - /** Used to insert the data object variable into compiled template source */ - var reInsertVariable = /(?:__e|__t = )\(\s*(?![\d\s"']|this\.)/g; + /** Used to detected named functions */ + var reFuncName = /^function[ \n\r\t]+\w/; - /** Used to detect if a method is native */ - var reNative = RegExp('^' + - (ObjectProto.valueOf + '') - .replace(/[.*+?^=!:${}()|[\]\/\\]/g, '\\$&') - .replace(/valueOf|for [^\]]+/g, '.+?') + '$' - ); + /** Used to match "interpolate" template delimiters */ + var reInterpolate = /<%=([\s\S]+?)%>/g; + + /** Used to match leading whitespace and zeros to be removed */ + var reLeadingSpacesAndZeros = RegExp('^[' + whitespace + ']*0+(?=.$)'); - /** Used to match internally used tokens in template text */ - var reToken = /__token(\d+)__/g; + /** Used to ensure capturing order of template delimiters */ + var reNoMatch = /($^)/; - /** Used to match HTML characters */ - var reUnescapedHtml = /[&<>"']/g; + /** Used to detect functions containing a `this` reference */ + var reThis = /\bthis\b/; /** Used to match unescaped characters in compiled string literals */ var reUnescapedString = /['\n\r\t\u2028\u2029\\]/g; + /** Used to assign default `context` object properties */ + var contextProps = [ + 'Array', 'Boolean', 'Date', 'Error', 'Function', 'Math', 'Number', 'Object', + 'RegExp', 'String', '_', 'attachEvent', 'clearTimeout', 'isFinite', 'isNaN', + 'parseInt', 'setImmediate', 'setTimeout' + ]; + /** Used to fix the JScript [[DontEnum]] bug */ - var shadowed = [ + var shadowedProps = [ 'constructor', 'hasOwnProperty', 'isPrototypeOf', 'propertyIsEnumerable', 'toLocaleString', 'toString', 'valueOf' ]; @@ -95,171 +91,54 @@ /** Used to make template sourceURLs easier to identify */ var templateCounter = 0; - /** Used to replace template delimiters */ - var tokenHead = '__token', - tokenFoot = '__'; - - /** Used to store tokenized template text snippets */ - var tokenized = []; - - /** Native method shortcuts */ - var concat = ArrayProto.concat, - hasOwnProperty = ObjectProto.hasOwnProperty, - push = ArrayProto.push, - propertyIsEnumerable = ObjectProto.propertyIsEnumerable, - slice = ArrayProto.slice, - toString = ObjectProto.toString; - - /* Native method shortcuts for methods with the same name as other `lodash` methods */ - var nativeBind = reNative.test(nativeBind = slice.bind) && nativeBind, - nativeFloor = Math.floor, - nativeIsArray = reNative.test(nativeIsArray = Array.isArray) && nativeIsArray, - nativeIsFinite = window.isFinite, - nativeKeys = reNative.test(nativeKeys = Object.keys) && nativeKeys, - nativeMax = Math.max, - nativeMin = Math.min, - nativeRandom = Math.random; - /** `Object#toString` result shortcuts */ var argsClass = '[object Arguments]', arrayClass = '[object Array]', boolClass = '[object Boolean]', dateClass = '[object Date]', + errorClass = '[object Error]', funcClass = '[object Function]', numberClass = '[object Number]', objectClass = '[object Object]', regexpClass = '[object RegExp]', stringClass = '[object String]'; - /** Timer shortcuts */ - var clearTimeout = window.clearTimeout, - setTimeout = window.setTimeout; - - /** - * Detect the JScript [[DontEnum]] bug: - * - * In IE < 9 an objects own properties, shadowing non-enumerable ones, are - * made non-enumerable as well. - */ - var hasDontEnumBug; - - /** - * Detect if `Array#shift` and `Array#splice` augment array-like objects - * incorrectly: - * - * Firefox < 10, IE compatibility mode, and IE < 9 have buggy Array `shift()` - * and `splice()` functions that fail to remove the last element, `value[0]`, - * of array-like objects even though the `length` property is set to `0`. - * The `shift()` method is buggy in IE 8 compatibility mode, while `splice()` - * is buggy regardless of mode in IE < 9 and buggy in compatibility mode in IE 9. - */ - var hasObjectSpliceBug; - - /** Detect if own properties are iterated after inherited properties (IE < 9) */ - var iteratesOwnLast; - - /** Detect if an `arguments` object's indexes are non-enumerable (IE < 9) */ - var noArgsEnum = true; - - (function() { - var object = { '0': 1, 'length': 1 }, - props = []; - - function ctor() { this.x = 1; } - ctor.prototype = { 'valueOf': 1, 'y': 1 }; - for (var prop in new ctor) { props.push(prop); } - for (prop in arguments) { noArgsEnum = !prop; } - - hasDontEnumBug = (props + '').length < 4; - iteratesOwnLast = props[0] != 'x'; - hasObjectSpliceBug = (props.splice.call(object, 0, 1), object[0]); - }(1)); - - /** Detect if an `arguments` object's [[Class]] is unresolvable (Firefox < 4, IE < 9) */ - var noArgsClass = !isArguments(arguments); - - /** Detect if `Array#slice` cannot be used to convert strings to arrays (Opera < 10.52) */ - var noArraySliceOnStrings = slice.call('x')[0] != 'x'; - - /** - * Detect lack of support for accessing string characters by index: - * - * IE < 8 can't access characters by index and IE 8 can only access - * characters by index on string literals. - */ - var noCharByIndex = ('x'[0] + Object('x')[0]) != 'xx'; - - /** - * Detect if a node's [[Class]] is unresolvable (IE < 9) - * and that the JS engine won't error when attempting to coerce an object to - * a string without a `toString` property value of `typeof` "function". - */ - try { - var noNodeClass = ({ 'toString': 0 } + '', toString.call(window.document || 0) == objectClass); - } catch(e) { } - - /* Detect if `Function#bind` exists and is inferred to be fast (all but V8) */ - var isBindFast = nativeBind && /\n|Opera/.test(nativeBind + toString.call(window.opera)); - - /* Detect if `Object.keys` exists and is inferred to be fast (IE, Opera, V8) */ - var isKeysFast = nativeKeys && /^.+$|true/.test(nativeKeys + !!window.attachEvent); - - /* Detect if strict mode, "use strict", is inferred to be fast (V8) */ - var isStrictFast = !isBindFast; - - /** - * Detect if sourceURL syntax is usable without erroring: - * - * The JS engine in Adobe products, like InDesign, will throw a syntax error - * when it encounters a single line comment beginning with the `@` symbol. - * - * The JS engine in Narwhal will generate the function `function anonymous(){//}` - * and throw a syntax error. - * - * Avoid comments beginning `@` symbols in IE because they are part of its - * non-standard conditional compilation support. - * http://msdn.microsoft.com/en-us/library/121hztk3(v=vs.94).aspx - */ - try { - var useSourceURL = (Function('//@')(), !window.attachEvent); - } catch(e) { } - - /** Used to identify object classifications that are array-like */ - var arrayLikeClasses = {}; - arrayLikeClasses[boolClass] = arrayLikeClasses[dateClass] = arrayLikeClasses[funcClass] = - arrayLikeClasses[numberClass] = arrayLikeClasses[objectClass] = arrayLikeClasses[regexpClass] = false; - arrayLikeClasses[argsClass] = arrayLikeClasses[arrayClass] = arrayLikeClasses[stringClass] = true; - /** Used to identify object classifications that `_.clone` supports */ var cloneableClasses = {}; - cloneableClasses[argsClass] = cloneableClasses[funcClass] = false; - cloneableClasses[arrayClass] = cloneableClasses[boolClass] = cloneableClasses[dateClass] = - cloneableClasses[numberClass] = cloneableClasses[objectClass] = cloneableClasses[regexpClass] = - cloneableClasses[stringClass] = true; + cloneableClasses[funcClass] = false; + cloneableClasses[argsClass] = cloneableClasses[arrayClass] = + cloneableClasses[boolClass] = cloneableClasses[dateClass] = + cloneableClasses[numberClass] = cloneableClasses[objectClass] = + cloneableClasses[regexpClass] = cloneableClasses[stringClass] = true; + + /** Used as an internal `_.debounce` options object */ + var debounceOptions = { + 'leading': false, + 'maxWait': 0, + 'trailing': false + }; - /** - * Used to convert characters to HTML entities: - * - * Though the `>` character is escaped for symmetry, characters like `>` and `/` - * don't require escaping in HTML and have no special meaning unless they're part - * of a tag or an unquoted attribute value. - * http://mathiasbynens.be/notes/ambiguous-ampersands (under "semi-related fun fact") - */ - var htmlEscapes = { - '&': '&', - '<': '<', - '>': '>', - '"': '"', - "'": ''' + /** Used as the property descriptor for `__bindData__` */ + var descriptor = { + 'configurable': false, + 'enumerable': false, + 'value': null, + 'writable': false }; - /** Used to convert HTML entities to characters */ - var htmlUnescapes = { - '&': '&', - '<': '<', - '>': '>', - '"': '"', - ''': "'" + /** Used as the data object for `iteratorTemplate` */ + var iteratorData = { + 'args': '', + 'array': null, + 'bottom': '', + 'firstArg': '', + 'init': '', + 'keys': null, + 'loop': '', + 'shadowedProps': null, + 'support': null, + 'top': '', + 'useHas': false }; /** Used to determine if values are of the language type Object */ @@ -269,8 +148,7 @@ 'object': true, 'number': false, 'string': false, - 'undefined': false, - 'unknown': true + 'undefined': false }; /** Used to escape characters for inclusion in compiled string literals */ @@ -284,502 +162,174 @@ '\u2029': 'u2029' }; - /*--------------------------------------------------------------------------*/ - - /** - * The `lodash` function. - * - * @name _ - * @constructor - * @param {Mixed} value The value to wrap in a `LoDash` instance. - * @returns {Object} Returns a `LoDash` instance. - */ - function lodash(value) { - // allow invoking `lodash` without the `new` operator - return new LoDash(value); - } - - /** - * Creates a `LoDash` instance that wraps a value to allow chaining. - * - * @private - * @constructor - * @param {Mixed} value The value to wrap. - */ - function LoDash(value) { - // exit early if already wrapped - if (value && value.__wrapped__) { - return value; - } - this.__wrapped__ = value; - } - - /** - * By default, the template delimiters used by Lo-Dash are similar to those in - * embedded Ruby (ERB). Change the following template settings to use alternative - * delimiters. - * - * @static - * @memberOf _ - * @type Object - */ - lodash.templateSettings = { + /** Used as a reference to the global object */ + var root = (objectTypes[typeof window] && window) || this; - /** - * Used to detect `data` property values to be HTML-escaped. - * - * @static - * @memberOf _.templateSettings - * @type RegExp - */ - 'escape': /<%-([\s\S]+?)%>/g, + /** Detect free variable `exports` */ + var freeExports = objectTypes[typeof exports] && exports && !exports.nodeType && exports; - /** - * Used to detect code to be evaluated. - * - * @static - * @memberOf _.templateSettings - * @type RegExp - */ - 'evaluate': /<%([\s\S]+?)%>/g, + /** Detect free variable `module` */ + var freeModule = objectTypes[typeof module] && module && !module.nodeType && module; - /** - * Used to detect `data` property values to inject. - * - * @static - * @memberOf _.templateSettings - * @type RegExp - */ - 'interpolate': /<%=([\s\S]+?)%>/g, + /** Detect the popular CommonJS extension `module.exports` */ + var moduleExports = freeModule && freeModule.exports === freeExports && freeExports; - /** - * Used to reference the data object in the template text. - * - * @static - * @memberOf _.templateSettings - * @type String - */ - 'variable': '' - }; + /** Detect free variable `global` from Node.js or Browserified code and use it as `root` */ + var freeGlobal = objectTypes[typeof global] && global; + if (freeGlobal && (freeGlobal.global === freeGlobal || freeGlobal.window === freeGlobal)) { + root = freeGlobal; + } /*--------------------------------------------------------------------------*/ /** - * The template used to create iterator functions. + * The base implementation of `_.indexOf` without support for binary searches + * or `fromIndex` constraints. * * @private - * @param {Obect} data The data object used to populate the text. - * @returns {String} Returns the interpolated text. + * @param {Array} array The array to search. + * @param {*} value The value to search for. + * @param {number} [fromIndex=0] The index to search from. + * @returns {number} Returns the index of the matched value or `-1`. */ - var iteratorTemplate = template( - // conditional strict mode - '<% if (useStrict) { %>\'use strict\';\n<% } %>' + - - // the `iteratee` may be reassigned by the `top` snippet - 'var index, value, iteratee = <%= firstArg %>, ' + - // assign the `result` variable an initial value - 'result<% if (init) { %> = <%= init %><% } %>;\n' + - // add code to exit early or do so if the first argument is falsey - '<%= exit %>;\n' + - // add code after the exit snippet but before the iteration branches - '<%= top %>;\n' + - - // the following branch is for iterating arrays and array-like objects - '<% if (arrayBranch) { %>' + - 'var length = iteratee.length; index = -1;' + - ' <% if (objectBranch) { %>\nif (length > -1 && length === length >>> 0) {<% } %>' + - - // add support for accessing string characters by index if needed - ' <% if (noCharByIndex) { %>\n' + - ' if (toString.call(iteratee) == stringClass) {\n' + - ' iteratee = iteratee.split(\'\')\n' + - ' }' + - ' <% } %>\n' + - - ' <%= arrayBranch.beforeLoop %>;\n' + - ' while (++index < length) {\n' + - ' value = iteratee[index];\n' + - ' <%= arrayBranch.inLoop %>\n' + - ' }' + - ' <% if (objectBranch) { %>\n}<% } %>' + - '<% } %>' + - - // the following branch is for iterating an object's own/inherited properties - '<% if (objectBranch) { %>' + - ' <% if (arrayBranch) { %>\nelse {' + - - // add support for iterating over `arguments` objects if needed - ' <% } else if (noArgsEnum) { %>\n' + - ' var length = iteratee.length; index = -1;\n' + - ' if (length && isArguments(iteratee)) {\n' + - ' while (++index < length) {\n' + - ' value = iteratee[index += \'\'];\n' + - ' <%= objectBranch.inLoop %>\n' + - ' }\n' + - ' } else {' + - ' <% } %>' + - - // Firefox < 3.6, Opera > 9.50 - Opera < 11.60, and Safari < 5.1 - // (if the prototype or a property on the prototype has been set) - // incorrectly sets a function's `prototype` property [[Enumerable]] - // value to `true`. Because of this Lo-Dash standardizes on skipping - // the the `prototype` property of functions regardless of its - // [[Enumerable]] value. - ' <% if (!hasDontEnumBug) { %>\n' + - ' var skipProto = typeof iteratee == \'function\' && \n' + - ' propertyIsEnumerable.call(iteratee, \'prototype\');\n' + - ' <% } %>' + - - // iterate own properties using `Object.keys` if it's fast - ' <% if (isKeysFast && useHas) { %>\n' + - ' var ownIndex = -1,\n' + - ' ownProps = objectTypes[typeof iteratee] ? nativeKeys(iteratee) : [],\n' + - ' length = ownProps.length;\n\n' + - ' <%= objectBranch.beforeLoop %>;\n' + - ' while (++ownIndex < length) {\n' + - ' index = ownProps[ownIndex];\n' + - ' <% if (!hasDontEnumBug) { %>if (!(skipProto && index == \'prototype\')) {\n <% } %>' + - ' value = iteratee[index];\n' + - ' <%= objectBranch.inLoop %>\n' + - ' <% if (!hasDontEnumBug) { %>}\n<% } %>' + - ' }' + - - // else using a for-in loop - ' <% } else { %>\n' + - ' <%= objectBranch.beforeLoop %>;\n' + - ' for (index in iteratee) {<%' + - ' if (!hasDontEnumBug || useHas) { %>\n if (<%' + - ' if (!hasDontEnumBug) { %>!(skipProto && index == \'prototype\')<% }' + - ' if (!hasDontEnumBug && useHas) { %> && <% }' + - ' if (useHas) { %>hasOwnProperty.call(iteratee, index)<% }' + - ' %>) {' + - ' <% } %>\n' + - ' value = iteratee[index];\n' + - ' <%= objectBranch.inLoop %>;\n' + - ' <% if (!hasDontEnumBug || useHas) { %>}\n<% } %>' + - ' }' + - ' <% } %>' + - - // Because IE < 9 can't set the `[[Enumerable]]` attribute of an - // existing property and the `constructor` property of a prototype - // defaults to non-enumerable, Lo-Dash skips the `constructor` - // property when it infers it's iterating over a `prototype` object. - ' <% if (hasDontEnumBug) { %>\n\n' + - ' var ctor = iteratee.constructor;\n' + - ' <% for (var k = 0; k < 7; k++) { %>\n' + - ' index = \'<%= shadowed[k] %>\';\n' + - ' if (<%' + - ' if (shadowed[k] == \'constructor\') {' + - ' %>!(ctor && ctor.prototype === iteratee) && <%' + - ' } %>hasOwnProperty.call(iteratee, index)) {\n' + - ' value = iteratee[index];\n' + - ' <%= objectBranch.inLoop %>\n' + - ' }' + - ' <% } %>' + - ' <% } %>' + - ' <% if (arrayBranch || noArgsEnum) { %>\n}<% } %>' + - '<% } %>\n' + - - // add code to the bottom of the iteration function - '<%= bottom %>;\n' + - // finally, return the `result` - 'return result' - ); + function baseIndexOf(array, value, fromIndex) { + var index = (fromIndex || 0) - 1, + length = array ? array.length : 0; + + while (++index < length) { + if (array[index] === value) { + return index; + } + } + return -1; + } /** - * Reusable iterator options shared by - * `every`, `filter`, `find`, `forEach`, `forIn`, `forOwn`, `groupBy`, `map`, - * `reject`, `some`, and `sortBy`. + * An implementation of `_.contains` for cache objects that mimics the return + * signature of `_.indexOf` by returning `0` if the value is found, else `-1`. + * + * @private + * @param {Object} cache The cache object to inspect. + * @param {*} value The value to search for. + * @returns {number} Returns `0` if `value` is found, else `-1`. */ - var baseIteratorOptions = { - 'args': 'collection, callback, thisArg', - 'init': 'collection', - 'top': - 'if (!callback) {\n' + - ' callback = identity\n' + - '}\n' + - 'else if (thisArg) {\n' + - ' callback = iteratorBind(callback, thisArg)\n' + - '}', - 'inLoop': 'if (callback(value, index, collection) === false) return result' - }; - - /** Reusable iterator options for `countBy`, `groupBy`, and `sortBy` */ - var countByIteratorOptions = { - 'init': '{}', - 'top': - 'var prop;\n' + - 'if (typeof callback != \'function\') {\n' + - ' var valueProp = callback;\n' + - ' callback = function(value) { return value[valueProp] }\n' + - '}\n' + - 'else if (thisArg) {\n' + - ' callback = iteratorBind(callback, thisArg)\n' + - '}', - 'inLoop': - 'prop = callback(value, index, collection);\n' + - '(hasOwnProperty.call(result, prop) ? result[prop]++ : result[prop] = 1)' - }; - - /** Reusable iterator options for `every` and `some` */ - var everyIteratorOptions = { - 'init': 'true', - 'inLoop': 'if (!callback(value, index, collection)) return !result' - }; - - /** Reusable iterator options for `defaults` and `extend` */ - var extendIteratorOptions = { - 'useHas': false, - 'useStrict': false, - 'args': 'object', - 'init': 'object', - 'top': - 'for (var argsIndex = 1, argsLength = arguments.length; argsIndex < argsLength; argsIndex++) {\n' + - ' if (iteratee = arguments[argsIndex]) {', - 'inLoop': 'result[index] = value', - 'bottom': ' }\n}' - }; + function cacheIndexOf(cache, value) { + var type = typeof value; + cache = cache.cache; - /** Reusable iterator options for `filter`, `reject`, and `where` */ - var filterIteratorOptions = { - 'init': '[]', - 'inLoop': 'callback(value, index, collection) && result.push(value)' - }; - - /** Reusable iterator options for `find`, `forEach`, `forIn`, and `forOwn` */ - var forEachIteratorOptions = { - 'top': 'if (thisArg) callback = iteratorBind(callback, thisArg)' - }; - - /** Reusable iterator options for `forIn` and `forOwn` */ - var forOwnIteratorOptions = { - 'inLoop': { - 'object': baseIteratorOptions.inLoop + if (type == 'boolean' || value == null) { + return cache[value] ? 0 : -1; } - }; - - /** Reusable iterator options for `invoke`, `map`, `pluck`, and `sortBy` */ - var mapIteratorOptions = { - 'init': '', - 'exit': 'if (!collection) return []', - 'beforeLoop': { - 'array': 'result = Array(length)', - 'object': 'result = ' + (isKeysFast ? 'Array(length)' : '[]') - }, - 'inLoop': { - 'array': 'result[index] = callback(value, index, collection)', - 'object': 'result' + (isKeysFast ? '[ownIndex] = ' : '.push') + '(callback(value, index, collection))' + if (type != 'number' && type != 'string') { + type = 'object'; } - }; + var key = type == 'number' ? value : keyPrefix + value; + cache = (cache = cache[type]) && cache[key]; - /** Reusable iterator options for `omit` and `pick` */ - var omitIteratorOptions = { - 'useHas': false, - 'args': 'object, callback, thisArg', - 'init': '{}', - 'top': - 'var isFunc = typeof callback == \'function\';\n' + - 'if (!isFunc) {\n' + - ' var props = concat.apply(ArrayProto, arguments)\n' + - '} else if (thisArg) {\n' + - ' callback = iteratorBind(callback, thisArg)\n' + - '}', - 'inLoop': - 'if (isFunc\n' + - ' ? !callback(value, index, object)\n' + - ' : indexOf(props, index) < 0\n' + - ') result[index] = value' - }; - - /*--------------------------------------------------------------------------*/ + return type == 'object' + ? (cache && baseIndexOf(cache, value) > -1 ? 0 : -1) + : (cache ? 0 : -1); + } /** - * Creates a new function optimized for searching large arrays for a given `value`, - * starting at `fromIndex`, using strict equality for comparisons, i.e. `===`. + * Adds a given value to the corresponding cache object. * * @private - * @param {Array} array The array to search. - * @param {Mixed} value The value to search for. - * @param {Number} [fromIndex=0] The index to start searching from. - * @param {Number} [largeSize=30] The length at which an array is considered large. - * @returns {Boolean} Returns `true` if `value` is found, else `false`. + * @param {*} value The value to add to the cache. */ - function cachedContains(array, fromIndex, largeSize) { - fromIndex || (fromIndex = 0); - - var length = array.length, - isLarge = (length - fromIndex) >= (largeSize || largeArraySize), - cache = isLarge ? {} : array; + function cachePush(value) { + var cache = this.cache, + type = typeof value; - if (isLarge) { - // init value cache - var key, - index = fromIndex - 1; - - while (++index < length) { - // manually coerce `value` to string because `hasOwnProperty`, in some - // older versions of Firefox, coerces objects incorrectly - key = array[index] + ''; - (hasOwnProperty.call(cache, key) ? cache[key] : (cache[key] = [])).push(array[index]); + if (type == 'boolean' || value == null) { + cache[value] = true; + } else { + if (type != 'number' && type != 'string') { + type = 'object'; } - } - return function(value) { - if (isLarge) { - var key = value + ''; - return hasOwnProperty.call(cache, key) && indexOf(cache[key], value) > -1; + var key = type == 'number' ? value : keyPrefix + value, + typeCache = cache[type] || (cache[type] = {}); + + if (type == 'object') { + (typeCache[key] || (typeCache[key] = [])).push(value); + } else { + typeCache[key] = true; } - return indexOf(cache, value, fromIndex) > -1; } } /** - * Creates compiled iteration functions. The iteration function will be created - * to iterate over only objects if the first argument of `options.args` is - * "object" or `options.inLoop.array` is falsey. + * Used by `_.max` and `_.min` as the default callback when a given + * collection is a string value. * * @private - * @param {Object} [options1, options2, ...] The compile options objects. - * - * useHas - A boolean to specify whether or not to use `hasOwnProperty` checks - * in the object loop. - * - * useStrict - A boolean to specify whether or not to include the ES5 - * "use strict" directive. - * - * args - A string of comma separated arguments the iteration function will - * accept. - * - * init - A string to specify the initial value of the `result` variable. - * - * exit - A string of code to use in place of the default exit-early check - * of `if (!arguments[0]) return result`. - * - * top - A string of code to execute after the exit-early check but before - * the iteration branches. - * - * beforeLoop - A string or object containing an "array" or "object" property - * of code to execute before the array or object loops. - * - * inLoop - A string or object containing an "array" or "object" property - * of code to execute in the array or object loops. - * - * bottom - A string of code to execute after the iteration branches but - * before the `result` is returned. - * - * @returns {Function} Returns the compiled function. + * @param {string} value The character to inspect. + * @returns {number} Returns the code unit of given character. */ - function createIterator() { - var object, - prop, - value, - index = -1, - length = arguments.length; - - // merge options into a template data object - var data = { - 'bottom': '', - 'exit': '', - 'init': '', - 'top': '', - 'arrayBranch': { 'beforeLoop': '' }, - 'objectBranch': { 'beforeLoop': '' } - }; - - while (++index < length) { - object = arguments[index]; - for (prop in object) { - value = (value = object[prop]) == null ? '' : value; - // keep this regexp explicit for the build pre-process - if (/beforeLoop|inLoop/.test(prop)) { - if (typeof value == 'string') { - value = { 'array': value, 'object': value }; - } - data.arrayBranch[prop] = value.array || ''; - data.objectBranch[prop] = value.object || ''; - } else { - data[prop] = value; - } - } - } - // set additional template `data` values - var args = data.args, - firstArg = /^[^,]+/.exec(args)[0], - useStrict = data.useStrict; - - data.firstArg = firstArg; - data.hasDontEnumBug = hasDontEnumBug; - data.isKeysFast = isKeysFast; - data.noArgsEnum = noArgsEnum; - data.shadowed = shadowed; - data.useHas = data.useHas !== false; - data.useStrict = useStrict == null ? isStrictFast : useStrict; - - if (data.noCharByIndex == null) { - data.noCharByIndex = noCharByIndex; - } - if (!data.exit) { - data.exit = 'if (!' + firstArg + ') return result'; - } - if (firstArg != 'collection' || !data.arrayBranch.inLoop) { - data.arrayBranch = null; - } - // create the function factory - var factory = Function( - 'arrayLikeClasses, ArrayProto, bind, compareAscending, concat, forIn, ' + - 'hasOwnProperty, identity, indexOf, isArguments, isArray, isFunction, ' + - 'isPlainObject, iteratorBind, objectClass, objectTypes, nativeKeys, ' + - 'propertyIsEnumerable, slice, stringClass, toString', - 'var callee = function(' + args + ') {\n' + iteratorTemplate(data) + '\n};\n' + - 'return callee' - ); - // return the compiled function - return factory( - arrayLikeClasses, ArrayProto, bind, compareAscending, concat, forIn, - hasOwnProperty, identity, indexOf, isArguments, isArray, isFunction, - isPlainObject, iteratorBind, objectClass, objectTypes, nativeKeys, - propertyIsEnumerable, slice, stringClass, toString - ); + function charAtCallback(value) { + return value.charCodeAt(0); } /** - * Used by `sortBy` to compare transformed `collection` values, stable sorting + * Used by `sortBy` to compare transformed `collection` elements, stable sorting * them in ascending order. * * @private * @param {Object} a The object to compare to `b`. * @param {Object} b The object to compare to `a`. - * @returns {Number} Returns the sort order indicator of `1` or `-1`. + * @returns {number} Returns the sort order indicator of `1` or `-1`. */ function compareAscending(a, b) { - var ai = a.index, - bi = b.index; - - a = a.criteria; - b = b.criteria; + var ac = a.criteria, + bc = b.criteria; // ensure a stable sort in V8 and other engines // http://code.google.com/p/v8/issues/detail?id=90 - if (a !== b) { - if (a > b || a === undefined) { + if (ac !== bc) { + if (ac > bc || typeof ac == 'undefined') { return 1; } - if (a < b || b === undefined) { + if (ac < bc || typeof bc == 'undefined') { return -1; } } - return ai < bi ? -1 : 1; + // The JS engine embedded in Adobe applications like InDesign has a buggy + // `Array#sort` implementation that causes it, under certain circumstances, + // to return the same value for `a` and `b`. + // See https://github.com/jashkenas/underscore/pull/1247 + return a.index - b.index; } /** - * Used by `template` to replace tokens with their corresponding code snippets. + * Creates a cache object to optimize linear searches of large arrays. * * @private - * @param {String} match The matched token. - * @param {String} index The `tokenized` index of the code snippet. - * @returns {String} Returns the code snippet. + * @param {Array} [array=[]] The array to search. + * @returns {null|Object} Returns the cache object or `null` if caching should not be used. */ - function detokenize(match, index) { - return tokenized[index]; + function createCache(array) { + var index = -1, + length = array.length, + first = array[0], + mid = array[(length / 2) | 0], + last = array[length - 1]; + + if (first && typeof first == 'object' && + mid && typeof mid == 'object' && last && typeof last == 'object') { + return false; + } + var cache = getObject(); + cache['false'] = cache['null'] = cache['true'] = cache['undefined'] = false; + + var result = getObject(); + result.array = array; + result.cache = cache; + result.push = cachePush; + + while (++index < length) { + result.push(array[index]); + } + return result; } /** @@ -787,3676 +337,6385 @@ * string literals. * * @private - * @param {String} match The matched character to escape. - * @returns {String} Returns the escaped character. + * @param {string} match The matched character to escape. + * @returns {string} Returns the escaped character. */ function escapeStringChar(match) { return '\\' + stringEscapes[match]; } /** - * Used by `escape` to convert characters to HTML entities. + * Gets an array from the array pool or creates a new one if the pool is empty. * * @private - * @param {String} match The matched character to escape. - * @returns {String} Returns the escaped character. + * @returns {Array} The array from the pool. */ - function escapeHtmlChar(match) { - return htmlEscapes[match]; + function getArray() { + return arrayPool.pop() || []; } /** - * Creates a new function that, when called, invokes `func` with the `this` - * binding of `thisArg` and the arguments (value, index, object). + * Gets an object from the object pool or creates a new one if the pool is empty. * * @private - * @param {Function} func The function to bind. - * @param {Mixed} [thisArg] The `this` binding of `func`. - * @returns {Function} Returns the new bound function. + * @returns {Object} The object from the pool. */ - function iteratorBind(func, thisArg) { - return function(value, index, object) { - return func.call(thisArg, value, index, object); + function getObject() { + return objectPool.pop() || { + 'array': null, + 'cache': null, + 'criteria': null, + 'false': false, + 'index': 0, + 'null': false, + 'number': null, + 'object': null, + 'push': null, + 'string': null, + 'true': false, + 'undefined': false, + 'value': null }; } /** - * A no-operation function. + * Checks if `value` is a DOM node in IE < 9. * * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if the `value` is a DOM node, else `false`. */ - function noop() { - // no operation performed + function isNode(value) { + // IE < 9 presents DOM nodes as `Object` objects except they have `toString` + // methods that are `typeof` "string" and still can coerce nodes to strings + return typeof value.toString != 'function' && typeof (value + '') == 'string'; } /** - * Used by `template` to replace "escape" template delimiters with tokens. + * A no-operation function. * * @private - * @param {String} match The matched template delimiter. - * @param {String} value The delimiter value. - * @returns {String} Returns a token. */ - function tokenizeEscape(match, value) { - if (match && reComplexDelimiter.test(value)) { - return ''; - } - var index = tokenized.length; - tokenized[index] = "' +\n__e(" + value + ") +\n'"; - return tokenHead + index + tokenFoot; + function noop() { + // no operation performed } /** - * Used by `template` to replace "evaluate" template delimiters, or complex - * "escape" and "interpolate" delimiters, with tokens. + * Releases the given array back to the array pool. * * @private - * @param {String} match The matched template delimiter. - * @param {String} escapeValue The complex "escape" delimiter value. - * @param {String} interpolateValue The complex "interpolate" delimiter value. - * @param {String} [evaluateValue] The "evaluate" delimiter value. - * @returns {String} Returns a token. + * @param {Array} [array] The array to release. */ - function tokenizeEvaluate(match, escapeValue, interpolateValue, evaluateValue) { - if (evaluateValue) { - var index = tokenized.length; - tokenized[index] = "';\n" + evaluateValue + ";\n__p += '"; - return tokenHead + index + tokenFoot; - } - return escapeValue - ? tokenizeEscape(null, escapeValue) - : tokenizeInterpolate(null, interpolateValue); + function releaseArray(array) { + array.length = 0; + if (arrayPool.length < maxPoolSize) { + arrayPool.push(array); + } } /** - * Used by `template` to replace "interpolate" template delimiters with tokens. + * Releases the given object back to the object pool. * * @private - * @param {String} match The matched template delimiter. - * @param {String} value The delimiter value. - * @returns {String} Returns a token. + * @param {Object} [object] The object to release. */ - function tokenizeInterpolate(match, value) { - if (match && reComplexDelimiter.test(value)) { - return ''; + function releaseObject(object) { + var cache = object.cache; + if (cache) { + releaseObject(cache); + } + object.array = object.cache = object.criteria = object.object = object.number = object.string = object.value = null; + if (objectPool.length < maxPoolSize) { + objectPool.push(object); } - var index = tokenized.length; - tokenized[index] = "' +\n((__t = (" + value + ")) == null ? '' : __t) +\n'"; - return tokenHead + index + tokenFoot; } /** - * Used by `unescape` to convert HTML entities to characters. + * Slices the `collection` from the `start` index up to, but not including, + * the `end` index. + * + * Note: This function is used instead of `Array#slice` to support node lists + * in IE < 9 and to ensure dense arrays are returned. * * @private - * @param {String} match The matched character to unescape. - * @returns {String} Returns the unescaped character. + * @param {Array|Object|string} collection The collection to slice. + * @param {number} start The start index. + * @param {number} end The end index. + * @returns {Array} Returns the new array. */ - function unescapeHtmlChar(match) { - return htmlUnescapes[match]; + function slice(array, start, end) { + start || (start = 0); + if (typeof end == 'undefined') { + end = array ? array.length : 0; + } + var index = -1, + length = end - start || 0, + result = Array(length < 0 ? 0 : length); + + while (++index < length) { + result[index] = array[start + index]; + } + return result; } /*--------------------------------------------------------------------------*/ /** - * Checks if `value` is an `arguments` object. + * Create a new `lodash` function using the given context object. * * @static * @memberOf _ - * @category Objects - * @param {Mixed} value The value to check. - * @returns {Boolean} Returns `true` if the `value` is an `arguments` object, else `false`. - * @example - * - * (function() { return _.isArguments(arguments); })(1, 2, 3); - * // => true - * - * _.isArguments([1, 2, 3]); - * // => false + * @category Utilities + * @param {Object} [context=root] The context object. + * @returns {Function} Returns the `lodash` function. */ - function isArguments(value) { - return toString.call(value) == argsClass; - } - // fallback for browsers that can't detect `arguments` objects by [[Class]] - if (noArgsClass) { - isArguments = function(value) { - return !!(value && hasOwnProperty.call(value, 'callee')); - }; - } + function runInContext(context) { + // Avoid issues with some ES3 environments that attempt to use values, named + // after built-in constructors like `Object`, for the creation of literals. + // ES5 clears this up by stating that literals must use built-in constructors. + // See http://es5.github.io/#x11.1.5. + context = context ? _.defaults(root.Object(), context, _.pick(root, contextProps)) : root; + + /** Native constructor references */ + var Array = context.Array, + Boolean = context.Boolean, + Date = context.Date, + Error = context.Error, + Function = context.Function, + Math = context.Math, + Number = context.Number, + Object = context.Object, + RegExp = context.RegExp, + String = context.String, + TypeError = context.TypeError; - /** - * Checks if `value` is an array. - * - * @static - * @memberOf _ - * @category Objects - * @param {Mixed} value The value to check. - * @returns {Boolean} Returns `true` if the `value` is an array, else `false`. - * @example - * - * (function() { return _.isArray(arguments); })(); - * // => false - * - * _.isArray([1, 2, 3]); - * // => true - */ - var isArray = nativeIsArray || function(value) { - return toString.call(value) == arrayClass; - }; + /** + * Used for `Array` method references. + * + * Normally `Array.prototype` would suffice, however, using an array literal + * avoids issues in Narwhal. + */ + var arrayRef = []; - /** - * Checks if `value` is a function. - * - * @static - * @memberOf _ - * @category Objects - * @param {Mixed} value The value to check. - * @returns {Boolean} Returns `true` if the `value` is a function, else `false`. - * @example - * - * _.isFunction(''.concat); - * // => true - */ - function isFunction(value) { - return typeof value == 'function'; - } - // fallback for older versions of Chrome and Safari - if (isFunction(/x/)) { - isFunction = function(value) { - return toString.call(value) == funcClass; - }; - } + /** Used for native method references */ + var errorProto = Error.prototype, + objectProto = Object.prototype, + stringProto = String.prototype; - /** - * A fallback implementation of `isPlainObject` that checks if a given `value` - * is an object created by the `Object` constructor, assuming objects created - * by the `Object` constructor have no inherited enumerable properties and that - * there are no `Object.prototype` extensions. - * - * @private - * @param {Mixed} value The value to check. - * @param {Boolean} [skipArgsCheck=false] Internally used to skip checks for - * `arguments` objects. - * @returns {Boolean} Returns `true` if `value` is a plain object, else `false`. - */ - function isPlainFallback(value, skipArgsCheck) { - // avoid non-objects and false positives for `arguments` objects - var result = false; - if (!(value && typeof value == 'object') || (!skipArgsCheck && isArguments(value))) { - return result; - } - // IE < 9 presents DOM nodes as `Object` objects except they have `toString` - // methods that are `typeof` "string" and still can coerce nodes to strings. - // Also check that the constructor is `Object` (i.e. `Object instanceof Object`) - var ctor = value.constructor; - if ((!noNodeClass || !(typeof value.toString != 'function' && typeof (value + '') == 'string')) && - (!isFunction(ctor) || ctor instanceof ctor)) { - // IE < 9 iterates inherited properties before own properties. If the first - // iterated property is an object's own property then there are no inherited - // enumerable properties. - if (iteratesOwnLast) { - forIn(value, function(value, key, object) { - result = !hasOwnProperty.call(object, key); - return false; - }); - return result === false; - } - // In most environments an object's own properties are iterated before - // its inherited properties. If the last iterated property is an object's - // own property then there are no inherited enumerable properties. - forIn(value, function(value, key) { - result = key; - }); - return result === false || hasOwnProperty.call(value, result); - } - return result; - } + /** Used to restore the original `_` reference in `noConflict` */ + var oldDash = context._; - /** - * Checks if a given `value` is an object created by the `Object` constructor. - * - * @private - * @param {Mixed} value The value to check. - * @param {Boolean} [skipArgsCheck=false] Internally used to skip checks for - * `arguments` objects. - * @returns {Boolean} Returns `true` if `value` is a plain object, else `false`. - */ - var isPlainObject = objectTypes.__proto__ != ObjectProto ? isPlainFallback : function(value, skipArgsCheck) { - if (!value) { - return false; - } - var valueOf = value.valueOf, - objProto = typeof valueOf == 'function' && (objProto = valueOf.__proto__) && objProto.__proto__; + /** Used to detect if a method is native */ + var reNative = RegExp('^' + + String(objectProto.valueOf) + .replace(/[.*+?^${}()|[\]\\]/g, '\\$&') + .replace(/valueOf|for [^\]]+/g, '.+?') + '$' + ); - return objProto - ? value == objProto || (value.__proto__ == objProto && (skipArgsCheck || !isArguments(value))) - : isPlainFallback(value); - }; + /** Native method shortcuts */ + var ceil = Math.ceil, + clearTimeout = context.clearTimeout, + floor = Math.floor, + fnToString = Function.prototype.toString, + getPrototypeOf = reNative.test(getPrototypeOf = Object.getPrototypeOf) && getPrototypeOf, + hasOwnProperty = objectProto.hasOwnProperty, + now = reNative.test(now = Date.now) && now || function() { return +new Date; }, + push = arrayRef.push, + propertyIsEnumerable = objectProto.propertyIsEnumerable, + setImmediate = context.setImmediate, + setTimeout = context.setTimeout, + splice = arrayRef.splice, + toString = objectProto.toString, + unshift = arrayRef.unshift; + + var defineProperty = (function() { + try { + var o = {}, + func = reNative.test(func = Object.defineProperty) && func, + result = func(o, o, o) && func; + } catch(e) { } + return result; + }()); + + /* Native method shortcuts for methods with the same name as other `lodash` methods */ + var nativeBind = reNative.test(nativeBind = toString.bind) && nativeBind, + nativeCreate = reNative.test(nativeCreate = Object.create) && nativeCreate, + nativeIsArray = reNative.test(nativeIsArray = Array.isArray) && nativeIsArray, + nativeIsFinite = context.isFinite, + nativeIsNaN = context.isNaN, + nativeKeys = reNative.test(nativeKeys = Object.keys) && nativeKeys, + nativeMax = Math.max, + nativeMin = Math.min, + nativeParseInt = context.parseInt, + nativeRandom = Math.random, + nativeSlice = arrayRef.slice; + + /** Detect various environments */ + var isIeOpera = reNative.test(context.attachEvent), + isV8 = nativeBind && !/\n|true/.test(nativeBind + isIeOpera); + + /** Used to lookup a built-in constructor by [[Class]] */ + var ctorByClass = {}; + ctorByClass[arrayClass] = Array; + ctorByClass[boolClass] = Boolean; + ctorByClass[dateClass] = Date; + ctorByClass[funcClass] = Function; + ctorByClass[objectClass] = Object; + ctorByClass[numberClass] = Number; + ctorByClass[regexpClass] = RegExp; + ctorByClass[stringClass] = String; + + /** Used to avoid iterating non-enumerable properties in IE < 9 */ + var nonEnumProps = {}; + nonEnumProps[arrayClass] = nonEnumProps[dateClass] = nonEnumProps[numberClass] = { 'constructor': true, 'toLocaleString': true, 'toString': true, 'valueOf': true }; + nonEnumProps[boolClass] = nonEnumProps[stringClass] = { 'constructor': true, 'toString': true, 'valueOf': true }; + nonEnumProps[errorClass] = nonEnumProps[funcClass] = nonEnumProps[regexpClass] = { 'constructor': true, 'toString': true }; + nonEnumProps[objectClass] = { 'constructor': true }; + + (function() { + var length = shadowedProps.length; + while (length--) { + var prop = shadowedProps[length]; + for (var className in nonEnumProps) { + if (hasOwnProperty.call(nonEnumProps, className) && !hasOwnProperty.call(nonEnumProps[className], prop)) { + nonEnumProps[className][prop] = false; + } + } + } + }()); - /** - * A shim implementation of `Object.keys` that produces an array of the given - * object's own enumerable property names. - * - * @private - * @param {Object} object The object to inspect. - * @returns {Array} Returns a new array of property names. - */ - var shimKeys = createIterator({ - 'args': 'object', - 'init': '[]', - 'inLoop': 'result.push(index)' - }); + /*--------------------------------------------------------------------------*/ - /*--------------------------------------------------------------------------*/ - - /** - * Creates a clone of `value`. If `deep` is `true`, all nested objects will - * also be cloned otherwise they will be assigned by reference. If a value has - * a `clone` method it will be used to perform the clone. Functions, DOM nodes, - * `arguments` objects, and objects created by constructors other than `Object` - * are **not** cloned unless they have a custom `clone` method. - * - * @static - * @memberOf _ - * @category Objects - * @param {Mixed} value The value to clone. - * @param {Boolean} deep A flag to indicate a deep clone. - * @param {Object} [guard] Internally used to allow this method to work with - * others like `_.map` without using their callback `index` argument for `deep`. - * @param {Object} [data={}] Internally used to track traversed objects to avoid - * circular references and indicate whether to perform a more thorough clone - * of non-object values. - * @returns {Mixed} Returns the cloned `value`. - * @example - * - * var stooges = [ - * { 'name': 'moe', 'age': 40 }, - * { 'name': 'larry', 'age': 50 }, - * { 'name': 'curly', 'age': 60 } - * ]; - * - * _.clone({ 'name': 'moe' }); - * // => { 'name': 'moe' } - * - * var shallow = _.clone(stooges); - * shallow[0] === stooges[0]; - * // => true - * - * var deep = _.clone(stooges, true); - * shallow[0] === stooges[0]; - * // => false - */ - function clone(value, deep, guard, data) { - if (value == null) { - return value; - } - if (guard) { - deep = false; + /** + * Creates a `lodash` object which wraps the given value to enable intuitive + * method chaining. + * + * In addition to Lo-Dash methods, wrappers also have the following `Array` methods: + * `concat`, `join`, `pop`, `push`, `reverse`, `shift`, `slice`, `sort`, `splice`, + * and `unshift` + * + * Chaining is supported in custom builds as long as the `value` method is + * implicitly or explicitly included in the build. + * + * The chainable wrapper functions are: + * `after`, `assign`, `bind`, `bindAll`, `bindKey`, `chain`, `compact`, + * `compose`, `concat`, `countBy`, `createCallback`, `curry`, `debounce`, + * `defaults`, `defer`, `delay`, `difference`, `filter`, `flatten`, `forEach`, + * `forEachRight`, `forIn`, `forInRight`, `forOwn`, `forOwnRight`, `functions`, + * `groupBy`, `indexBy`, `initial`, `intersection`, `invert`, `invoke`, `keys`, + * `map`, `max`, `memoize`, `merge`, `min`, `object`, `omit`, `once`, `pairs`, + * `partial`, `partialRight`, `pick`, `pluck`, `pull`, `push`, `range`, `reject`, + * `remove`, `rest`, `reverse`, `shuffle`, `slice`, `sort`, `sortBy`, `splice`, + * `tap`, `throttle`, `times`, `toArray`, `transform`, `union`, `uniq`, `unshift`, + * `unzip`, `values`, `where`, `without`, `wrap`, and `zip` + * + * The non-chainable wrapper functions are: + * `clone`, `cloneDeep`, `contains`, `escape`, `every`, `find`, `findIndex`, + * `findKey`, `findLast`, `findLastIndex`, `findLastKey`, `has`, `identity`, + * `indexOf`, `isArguments`, `isArray`, `isBoolean`, `isDate`, `isElement`, + * `isEmpty`, `isEqual`, `isFinite`, `isFunction`, `isNaN`, `isNull`, `isNumber`, + * `isObject`, `isPlainObject`, `isRegExp`, `isString`, `isUndefined`, `join`, + * `lastIndexOf`, `mixin`, `noConflict`, `parseInt`, `pop`, `random`, `reduce`, + * `reduceRight`, `result`, `shift`, `size`, `some`, `sortedIndex`, `runInContext`, + * `template`, `unescape`, `uniqueId`, and `value` + * + * The wrapper functions `first` and `last` return wrapped values when `n` is + * provided, otherwise they return unwrapped values. + * + * Explicit chaining can be enabled by using the `_.chain` method. + * + * @name _ + * @constructor + * @category Chaining + * @param {*} value The value to wrap in a `lodash` instance. + * @returns {Object} Returns a `lodash` instance. + * @example + * + * var wrapped = _([1, 2, 3]); + * + * // returns an unwrapped value + * wrapped.reduce(function(sum, num) { + * return sum + num; + * }); + * // => 6 + * + * // returns a wrapped value + * var squares = wrapped.map(function(num) { + * return num * num; + * }); + * + * _.isArray(squares); + * // => false + * + * _.isArray(squares.value()); + * // => true + */ + function lodash(value) { + // don't wrap if already wrapped, even if wrapped by a different `lodash` constructor + return (value && typeof value == 'object' && !isArray(value) && hasOwnProperty.call(value, '__wrapped__')) + ? value + : new lodashWrapper(value); } - // init internal data - data || (data = { 'thorough': null }); - // avoid slower checks on primitives - if (data.thorough == null) { - // primitives passed from iframes use the primary document's native prototypes - data.thorough = !!(BoolProto.clone || NumberProto.clone || StringProto.clone); - } - // use custom `clone` method if available - var isObj = objectTypes[typeof value]; - if ((isObj || data.thorough) && value.clone && isFunction(value.clone)) { - data.thorough = null; - return value.clone(deep); + /** + * A fast path for creating `lodash` wrapper objects. + * + * @private + * @param {*} value The value to wrap in a `lodash` instance. + * @param {boolean} chainAll A flag to enable chaining for all methods + * @returns {Object} Returns a `lodash` instance. + */ + function lodashWrapper(value, chainAll) { + this.__chain__ = !!chainAll; + this.__wrapped__ = value; } - // inspect [[Class]] - if (isObj) { - // don't clone `arguments` objects, functions, or non-object Objects - var className = toString.call(value); - if (!cloneableClasses[className] || (noArgsClass && isArguments(value))) { - return value; + // ensure `new lodashWrapper` is an instance of `lodash` + lodashWrapper.prototype = lodash.prototype; + + /** + * An object used to flag environments features. + * + * @static + * @memberOf _ + * @type Object + */ + var support = lodash.support = {}; + + (function() { + var ctor = function() { this.x = 1; }, + object = { '0': 1, 'length': 1 }, + props = []; + + ctor.prototype = { 'valueOf': 1, 'y': 1 }; + for (var prop in new ctor) { props.push(prop); } + for (prop in arguments) { } + + /** + * Detect if an `arguments` object's [[Class]] is resolvable (all but Firefox < 4, IE < 9). + * + * @memberOf _.support + * @type boolean + */ + support.argsClass = toString.call(arguments) == argsClass; + + /** + * Detect if `arguments` objects are `Object` objects (all but Narwhal and Opera < 10.5). + * + * @memberOf _.support + * @type boolean + */ + support.argsObject = arguments.constructor == Object && !(arguments instanceof Array); + + /** + * Detect if `name` or `message` properties of `Error.prototype` are + * enumerable by default. (IE < 9, Safari < 5.1) + * + * @memberOf _.support + * @type boolean + */ + support.enumErrorProps = propertyIsEnumerable.call(errorProto, 'message') || propertyIsEnumerable.call(errorProto, 'name'); + + /** + * Detect if `prototype` properties are enumerable by default. + * + * Firefox < 3.6, Opera > 9.50 - Opera < 11.60, and Safari < 5.1 + * (if the prototype or a property on the prototype has been set) + * incorrectly sets a function's `prototype` property [[Enumerable]] + * value to `true`. + * + * @memberOf _.support + * @type boolean + */ + support.enumPrototypes = propertyIsEnumerable.call(ctor, 'prototype'); + + /** + * Detect if `Function#bind` exists and is inferred to be fast (all but V8). + * + * @memberOf _.support + * @type boolean + */ + support.fastBind = nativeBind && !isV8; + + /** + * Detect if functions can be decompiled by `Function#toString` + * (all but PS3 and older Opera mobile browsers & avoided in Windows 8 apps). + * + * @memberOf _.support + * @type boolean + */ + support.funcDecomp = !reNative.test(context.WinRTError) && reThis.test(runInContext); + + /** + * Detect if `Function#name` is supported (all but IE). + * + * @memberOf _.support + * @type boolean + */ + support.funcNames = typeof Function.name == 'string'; + + /** + * Detect if `arguments` object indexes are non-enumerable + * (Firefox < 4, IE < 9, PhantomJS, Safari < 5.1). + * + * @memberOf _.support + * @type boolean + */ + support.nonEnumArgs = prop != 0; + + /** + * Detect if properties shadowing those on `Object.prototype` are non-enumerable. + * + * In IE < 9 an objects own properties, shadowing non-enumerable ones, are + * made non-enumerable as well (a.k.a the JScript [[DontEnum]] bug). + * + * @memberOf _.support + * @type boolean + */ + support.nonEnumShadows = !/valueOf/.test(props); + + /** + * Detect if own properties are iterated after inherited properties (all but IE < 9). + * + * @memberOf _.support + * @type boolean + */ + support.ownLast = props[0] != 'x'; + + /** + * Detect if `Array#shift` and `Array#splice` augment array-like objects correctly. + * + * Firefox < 10, IE compatibility mode, and IE < 9 have buggy Array `shift()` + * and `splice()` functions that fail to remove the last element, `value[0]`, + * of array-like objects even though the `length` property is set to `0`. + * The `shift()` method is buggy in IE 8 compatibility mode, while `splice()` + * is buggy regardless of mode in IE < 9 and buggy in compatibility mode in IE 9. + * + * @memberOf _.support + * @type boolean + */ + support.spliceObjects = (arrayRef.splice.call(object, 0, 1), !object[0]); + + /** + * Detect lack of support for accessing string characters by index. + * + * IE < 8 can't access characters by index and IE 8 can only access + * characters by index on string literals. + * + * @memberOf _.support + * @type boolean + */ + support.unindexedChars = ('x'[0] + Object('x')[0]) != 'xx'; + + /** + * Detect if a DOM node's [[Class]] is resolvable (all but IE < 9) + * and that the JS engine errors when attempting to coerce an object to + * a string without a `toString` function. + * + * @memberOf _.support + * @type boolean + */ + try { + support.nodeClass = !(toString.call(document) == objectClass && !({ 'toString': 0 } + '')); + } catch(e) { + support.nodeClass = true; } - var isArr = className == arrayClass; - isObj = isArr || (className == objectClass ? isPlainObject(value, true) : isObj); - } - // shallow clone - if (!isObj || !deep) { - // don't clone functions - return isObj - ? (isArr ? slice.call(value) : extend({}, value)) - : value; - } + }(1)); - var ctor = value.constructor; - switch (className) { - case boolClass: - return new ctor(value == true); + /** + * By default, the template delimiters used by Lo-Dash are similar to those in + * embedded Ruby (ERB). Change the following template settings to use alternative + * delimiters. + * + * @static + * @memberOf _ + * @type Object + */ + lodash.templateSettings = { + + /** + * Used to detect `data` property values to be HTML-escaped. + * + * @memberOf _.templateSettings + * @type RegExp + */ + 'escape': /<%-([\s\S]+?)%>/g, + + /** + * Used to detect code to be evaluated. + * + * @memberOf _.templateSettings + * @type RegExp + */ + 'evaluate': /<%([\s\S]+?)%>/g, + + /** + * Used to detect `data` property values to inject. + * + * @memberOf _.templateSettings + * @type RegExp + */ + 'interpolate': reInterpolate, + + /** + * Used to reference the data object in the template text. + * + * @memberOf _.templateSettings + * @type string + */ + 'variable': '', + + /** + * Used to import variables into the compiled template. + * + * @memberOf _.templateSettings + * @type Object + */ + 'imports': { + + /** + * A reference to the `lodash` function. + * + * @memberOf _.templateSettings.imports + * @type Function + */ + '_': lodash + } + }; - case dateClass: - return new ctor(+value); + /*--------------------------------------------------------------------------*/ - case numberClass: - case stringClass: - return new ctor(value); + /** + * The template used to create iterator functions. + * + * @private + * @param {Object} data The data object used to populate the text. + * @returns {string} Returns the interpolated text. + */ + var iteratorTemplate = function(obj) { + + var __p = 'var index, iterable = ' + + (obj.firstArg) + + ', result = ' + + (obj.init) + + ';\nif (!iterable) return result;\n' + + (obj.top) + + ';'; + if (obj.array) { + __p += '\nvar length = iterable.length; index = -1;\nif (' + + (obj.array) + + ') { '; + if (support.unindexedChars) { + __p += '\n if (isString(iterable)) {\n iterable = iterable.split(\'\')\n } '; + } + __p += '\n while (++index < length) {\n ' + + (obj.loop) + + ';\n }\n}\nelse { '; + } else if (support.nonEnumArgs) { + __p += '\n var length = iterable.length; index = -1;\n if (length && isArguments(iterable)) {\n while (++index < length) {\n index += \'\';\n ' + + (obj.loop) + + ';\n }\n } else { '; + } + + if (support.enumPrototypes) { + __p += '\n var skipProto = typeof iterable == \'function\';\n '; + } + + if (support.enumErrorProps) { + __p += '\n var skipErrorProps = iterable === errorProto || iterable instanceof Error;\n '; + } + + var conditions = []; if (support.enumPrototypes) { conditions.push('!(skipProto && index == "prototype")'); } if (support.enumErrorProps) { conditions.push('!(skipErrorProps && (index == "message" || index == "name"))'); } + + if (obj.useHas && obj.keys) { + __p += '\n var ownIndex = -1,\n ownProps = objectTypes[typeof iterable] && keys(iterable),\n length = ownProps ? ownProps.length : 0;\n\n while (++ownIndex < length) {\n index = ownProps[ownIndex];\n'; + if (conditions.length) { + __p += ' if (' + + (conditions.join(' && ')) + + ') {\n '; + } + __p += + (obj.loop) + + '; '; + if (conditions.length) { + __p += '\n }'; + } + __p += '\n } '; + } else { + __p += '\n for (index in iterable) {\n'; + if (obj.useHas) { conditions.push("hasOwnProperty.call(iterable, index)"); } if (conditions.length) { + __p += ' if (' + + (conditions.join(' && ')) + + ') {\n '; + } + __p += + (obj.loop) + + '; '; + if (conditions.length) { + __p += '\n }'; + } + __p += '\n } '; + if (support.nonEnumShadows) { + __p += '\n\n if (iterable !== objectProto) {\n var ctor = iterable.constructor,\n isProto = iterable === (ctor && ctor.prototype),\n className = iterable === stringProto ? stringClass : iterable === errorProto ? errorClass : toString.call(iterable),\n nonEnum = nonEnumProps[className];\n '; + for (k = 0; k < 7; k++) { + __p += '\n index = \'' + + (obj.shadowedProps[k]) + + '\';\n if ((!(isProto && nonEnum[index]) && hasOwnProperty.call(iterable, index))'; + if (!obj.useHas) { + __p += ' || (!nonEnum[index] && iterable[index] !== objectProto[index])'; + } + __p += ') {\n ' + + (obj.loop) + + ';\n } '; + } + __p += '\n } '; + } + + } + + if (obj.array || support.nonEnumArgs) { + __p += '\n}'; + } + __p += + (obj.bottom) + + ';\nreturn result'; + + return __p + }; - case regexpClass: - return ctor(value.source, reFlags.exec(value)); - } + /*--------------------------------------------------------------------------*/ - var clones = data.clones || (data.clones = []), - sources = data.sources || (data.sources = []), - length = clones.length; + /** + * The base implementation of `_.clone` without argument juggling or support + * for `thisArg` binding. + * + * @private + * @param {*} value The value to clone. + * @param {boolean} [deep=false] Specify a deep clone. + * @param {Function} [callback] The function to customize cloning values. + * @param {Array} [stackA=[]] Tracks traversed source objects. + * @param {Array} [stackB=[]] Associates clones with source counterparts. + * @returns {*} Returns the cloned value. + */ + function baseClone(value, deep, callback, stackA, stackB) { + if (callback) { + var result = callback(value); + if (typeof result != 'undefined') { + return result; + } + } + // inspect [[Class]] + var isObj = isObject(value); + if (isObj) { + var className = toString.call(value); + if (!cloneableClasses[className] || (!support.nodeClass && isNode(value))) { + return value; + } + var ctor = ctorByClass[className]; + switch (className) { + case boolClass: + case dateClass: + return new ctor(+value); + + case numberClass: + case stringClass: + return new ctor(value); + + case regexpClass: + result = ctor(value.source, reFlags.exec(value)); + result.lastIndex = value.lastIndex; + return result; + } + } else { + return value; + } + var isArr = isArray(value); + if (deep) { + // check for circular references and return corresponding clone + var initedStack = !stackA; + stackA || (stackA = getArray()); + stackB || (stackB = getArray()); + + var length = stackA.length; + while (length--) { + if (stackA[length] == value) { + return stackB[length]; + } + } + result = isArr ? ctor(value.length) : {}; + } + else { + result = isArr ? slice(value) : assign({}, value); + } + // add array properties assigned by `RegExp#exec` + if (isArr) { + if (hasOwnProperty.call(value, 'index')) { + result.index = value.index; + } + if (hasOwnProperty.call(value, 'input')) { + result.input = value.input; + } + } + // exit for shallow clone + if (!deep) { + return result; + } + // add the source value to the stack of traversed objects + // and associate it with its clone + stackA.push(value); + stackB.push(result); + + // recursively populate clone (susceptible to call stack limits) + (isArr ? baseEach : forOwn)(value, function(objValue, key) { + result[key] = baseClone(objValue, deep, callback, stackA, stackB); + }); - // check for circular references and return corresponding clone - while (length--) { - if (sources[length] == value) { - return clones[length]; + if (initedStack) { + releaseArray(stackA); + releaseArray(stackB); } + return result; } - // init cloned object - var result = isArr ? ctor(length = value.length) : {}; - - // add current clone and original source value to the stack of traversed objects - clones.push(result); - sources.push(value); - - // recursively populate clone (susceptible to call stack limits) - if (isArr) { - var index = -1; - while (++index < length) { - result[index] = clone(value[index], deep, null, data); + /** + * The base implementation of `_.createCallback` without support for creating + * "_.pluck" or "_.where" style callbacks. + * + * @private + * @param {*} [func=identity] The value to convert to a callback. + * @param {*} [thisArg] The `this` binding of the created callback. + * @param {number} [argCount] The number of arguments the callback accepts. + * @returns {Function} Returns a callback function. + */ + function baseCreateCallback(func, thisArg, argCount) { + if (typeof func != 'function') { + return identity; } - } else { - forOwn(value, function(objValue, key) { - result[key] = clone(objValue, deep, null, data); - }); + // exit early if there is no `thisArg` + if (typeof thisArg == 'undefined') { + return func; + } + var bindData = func.__bindData__ || (support.funcNames && !func.name); + if (typeof bindData == 'undefined') { + var source = reThis && fnToString.call(func); + if (!support.funcNames && source && !reFuncName.test(source)) { + bindData = true; + } + if (support.funcNames || !bindData) { + // checks if `func` references the `this` keyword and stores the result + bindData = !support.funcDecomp || reThis.test(source); + setBindData(func, bindData); + } + } + // exit early if there are no `this` references or `func` is bound + if (bindData !== true && (bindData && bindData[1] & 1)) { + return func; + } + switch (argCount) { + case 1: return function(value) { + return func.call(thisArg, value); + }; + case 2: return function(a, b) { + return func.call(thisArg, a, b); + }; + case 3: return function(value, index, collection) { + return func.call(thisArg, value, index, collection); + }; + case 4: return function(accumulator, value, index, collection) { + return func.call(thisArg, accumulator, value, index, collection); + }; + } + return bind(func, thisArg); } - return result; - } - - /** - * Assigns enumerable properties of the default object(s) to the `destination` - * object for all `destination` properties that resolve to `null`/`undefined`. - * Once a property is set, additional defaults of the same property will be - * ignored. - * - * @static - * @memberOf _ - * @category Objects - * @param {Object} object The destination object. - * @param {Object} [default1, default2, ...] The default objects. - * @returns {Object} Returns the destination object. - * @example - * - * var iceCream = { 'flavor': 'chocolate' }; - * _.defaults(iceCream, { 'flavor': 'vanilla', 'sprinkles': 'rainbow' }); - * // => { 'flavor': 'chocolate', 'sprinkles': 'rainbow' } - */ - var defaults = createIterator(extendIteratorOptions, { - 'inLoop': 'if (result[index] == null) ' + extendIteratorOptions.inLoop - }); - - /** - * Assigns enumerable properties of the source object(s) to the `destination` - * object. Subsequent sources will overwrite propery assignments of previous - * sources. - * - * @static - * @memberOf _ - * @category Objects - * @param {Object} object The destination object. - * @param {Object} [source1, source2, ...] The source objects. - * @returns {Object} Returns the destination object. - * @example - * - * _.extend({ 'name': 'moe' }, { 'age': 40 }); - * // => { 'name': 'moe', 'age': 40 } - */ - var extend = createIterator(extendIteratorOptions); - - /** - * Iterates over `object`'s own and inherited enumerable properties, executing - * the `callback` for each property. The `callback` is bound to `thisArg` and - * invoked with 3 arguments; (value, key, object). Callbacks may exit iteration - * early by explicitly returning `false`. - * - * @static - * @memberOf _ - * @category Objects - * @param {Object} object The object to iterate over. - * @param {Function} callback The function called per iteration. - * @param {Mixed} [thisArg] The `this` binding for the callback. - * @returns {Object} Returns `object`. - * @example - * - * function Dog(name) { - * this.name = name; - * } - * - * Dog.prototype.bark = function() { - * alert('Woof, woof!'); - * }; - * - * _.forIn(new Dog('Dagny'), function(value, key) { - * alert(key); - * }); - * // => alerts 'name' and 'bark' (order is not guaranteed) - */ - var forIn = createIterator(baseIteratorOptions, forEachIteratorOptions, forOwnIteratorOptions, { - 'useHas': false - }); - - /** - * Iterates over `object`'s own enumerable properties, executing the `callback` - * for each property. The `callback` is bound to `thisArg` and invoked with 3 - * arguments; (value, key, object). Callbacks may exit iteration early by - * explicitly returning `false`. - * - * @static - * @memberOf _ - * @category Objects - * @param {Object} object The object to iterate over. - * @param {Function} callback The function called per iteration. - * @param {Mixed} [thisArg] The `this` binding for the callback. - * @returns {Object} Returns `object`. - * @example - * - * _.forOwn({ '0': 'zero', '1': 'one', 'length': 2 }, function(num, key) { - * alert(key); - * }); - * // => alerts '0', '1', and 'length' (order is not guaranteed) - */ - var forOwn = createIterator(baseIteratorOptions, forEachIteratorOptions, forOwnIteratorOptions); - - /** - * Creates a sorted array of all enumerable properties, own and inherited, - * of `object` that have function values. - * - * @static - * @memberOf _ - * @alias methods - * @category Objects - * @param {Object} object The object to inspect. - * @returns {Array} Returns a new array of property names that have function values. - * @example - * - * _.functions(_); - * // => ['all', 'any', 'bind', 'bindAll', 'clone', 'compact', 'compose', ...] - */ - var functions = createIterator({ - 'useHas': false, - 'args': 'object', - 'init': '[]', - 'inLoop': 'if (isFunction(value)) result.push(index)', - 'bottom': 'result.sort()' - }); - - /** - * Checks if the specified object `property` exists and is a direct property, - * instead of an inherited property. - * - * @static - * @memberOf _ - * @category Objects - * @param {Object} object The object to check. - * @param {String} property The property to check for. - * @returns {Boolean} Returns `true` if key is a direct property, else `false`. - * @example - * - * _.has({ 'a': 1, 'b': 2, 'c': 3 }, 'b'); - * // => true - */ - function has(object, property) { - return object ? hasOwnProperty.call(object, property) : false; - } - - /** - * Creates an object composed of the inverted keys and values of the given `object`. - * - * @static - * @memberOf _ - * @category Objects - * @param {Object} object The object to invert. - * @returns {Object} Returns the created inverted object. - * @example - * - * _.invert({ 'first': 'Moe', 'second': 'Larry', 'third': 'Curly' }); - * // => { 'Moe': 'first', 'Larry': 'second', 'Curly': 'third' } (order is not guaranteed) - */ - var invert = createIterator({ - 'args': 'object', - 'init': '{}', - 'inLoop': 'result[value] = index' - }); - - /** - * Checks if `value` is a boolean (`true` or `false`) value. - * - * @static - * @memberOf _ - * @category Objects - * @param {Mixed} value The value to check. - * @returns {Boolean} Returns `true` if the `value` is a boolean value, else `false`. - * @example - * - * _.isBoolean(null); - * // => false - */ - function isBoolean(value) { - return value === true || value === false || toString.call(value) == boolClass; - } - - /** - * Checks if `value` is a date. - * - * @static - * @memberOf _ - * @category Objects - * @param {Mixed} value The value to check. - * @returns {Boolean} Returns `true` if the `value` is a date, else `false`. - * @example - * - * _.isDate(new Date); - * // => true - */ - function isDate(value) { - return toString.call(value) == dateClass; - } - - /** - * Checks if `value` is a DOM element. - * - * @static - * @memberOf _ - * @category Objects - * @param {Mixed} value The value to check. - * @returns {Boolean} Returns `true` if the `value` is a DOM element, else `false`. - * @example - * - * _.isElement(document.body); - * // => true - */ - function isElement(value) { - return value ? value.nodeType === 1 : false; - } - /** - * Checks if `value` is empty. Arrays, strings, or `arguments` objects with a - * length of `0` and objects with no own enumerable properties are considered - * "empty". - * - * @static - * @memberOf _ - * @category Objects - * @param {Array|Object|String} value The value to inspect. - * @returns {Boolean} Returns `true` if the `value` is empty, else `false`. - * @example - * - * _.isEmpty([1, 2, 3]); - * // => false - * - * _.isEmpty({}); - * // => true - * - * _.isEmpty(''); - * // => true - */ - var isEmpty = createIterator({ - 'args': 'value', - 'init': 'true', - 'top': - 'var className = toString.call(value),\n' + - ' length = value.length;\n' + - 'if (arrayLikeClasses[className]' + - (noArgsClass ? ' || isArguments(value)' : '') + ' ||\n' + - ' (className == objectClass && length > -1 && length === length >>> 0 &&\n' + - ' isFunction(value.splice))' + - ') return !length', - 'inLoop': { - 'object': 'return false' - } - }); + /** + * The base implementation of `_.flatten` without support for callback + * shorthands or `thisArg` binding. + * + * @private + * @param {Array} array The array to flatten. + * @param {boolean} [isShallow=false] A flag to restrict flattening to a single level. + * @param {boolean} [isArgArrays=false] A flag to restrict flattening to arrays and `arguments` objects. + * @param {number} [fromIndex=0] The index to start from. + * @returns {Array} Returns a new flattened array. + */ + function baseFlatten(array, isShallow, isArgArrays, fromIndex) { + var index = (fromIndex || 0) - 1, + length = array ? array.length : 0, + result = []; - /** - * Performs a deep comparison between two values to determine if they are - * equivalent to each other. If a value has an `isEqual` method it will be - * used to perform the comparison. - * - * @static - * @memberOf _ - * @category Objects - * @param {Mixed} a The value to compare. - * @param {Mixed} b The other value to compare. - * @param {Object} [data={}] Internally used track traversed objects to avoid - * circular references and indicate whether to perform a more thorough comparison - * of non-object values. - * @returns {Boolean} Returns `true` if the values are equvalent, else `false`. - * @example - * - * var moe = { 'name': 'moe', 'luckyNumbers': [13, 27, 34] }; - * var clone = { 'name': 'moe', 'luckyNumbers': [13, 27, 34] }; - * - * moe == clone; - * // => false - * - * _.isEqual(moe, clone); - * // => true - */ - function isEqual(a, b, data) { - // a strict comparison is necessary because `null == undefined` - if (a == null || b == null) { - return a === b; - } - // init internal data - data || (data = { 'thorough': null }); - - // avoid slower checks on non-objects - if (data.thorough == null) { - // primitives passed from iframes use the primary document's native prototypes - data.thorough = !!(BoolProto.isEqual || NumberProto.isEqual || StringProto.isEqual); - } - if (objectTypes[typeof a] || objectTypes[typeof b] || data.thorough) { - // unwrap any LoDash wrapped values - a = a.__wrapped__ || a; - b = b.__wrapped__ || b; - - // use custom `isEqual` method if available - if (a.isEqual && isFunction(a.isEqual)) { - data.thorough = null; - return a.isEqual(b); - } - if (b.isEqual && isFunction(b.isEqual)) { - data.thorough = null; - return b.isEqual(a); - } - } - // exit early for identical values - if (a === b) { - // treat `+0` vs. `-0` as not equal - return a !== 0 || (1 / a == 1 / b); - } - // compare [[Class]] names - var className = toString.call(a); - if (className != toString.call(b)) { - return false; - } - switch (className) { - case boolClass: - case dateClass: - // coerce dates and booleans to numbers, dates to milliseconds and booleans - // to `1` or `0`, treating invalid dates coerced to `NaN` as not equal - return +a == +b; - - case numberClass: - // treat `NaN` vs. `NaN` as equal - return a != +a - ? b != +b - // but treat `+0` vs. `-0` as not equal - : (a == 0 ? (1 / a == 1 / b) : a == +b); - - case regexpClass: - case stringClass: - // coerce regexes to strings (http://es5.github.com/#x15.10.6.4) - // treat string primitives and their corresponding object instances as equal - return a == b + ''; - } - // exit early, in older browsers, if `a` is array-like but not `b` - var isArr = arrayLikeClasses[className]; - if (noArgsClass && !isArr && (isArr = isArguments(a)) && !isArguments(b)) { - return false; - } - // exit for functions and DOM nodes - if (!isArr && (className != objectClass || (noNodeClass && ( - (typeof a.toString != 'function' && typeof (a + '') == 'string') || - (typeof b.toString != 'function' && typeof (b + '') == 'string'))))) { - return false; - } + while (++index < length) { + var value = array[index]; - // assume cyclic structures are equal - // the algorithm for detecting cyclic structures is adapted from ES 5.1 - // section 15.12.3, abstract operation `JO` (http://es5.github.com/#x15.12.3) - var stackA = data.stackA || (data.stackA = []), - stackB = data.stackB || (data.stackB = []), - length = stackA.length; + if (value && typeof value == 'object' && typeof value.length == 'number' + && (isArray(value) || isArguments(value))) { + // recursively flatten arrays (susceptible to call stack limits) + if (!isShallow) { + value = baseFlatten(value, isShallow, isArgArrays); + } + var valIndex = -1, + valLength = value.length, + resIndex = result.length; - while (length--) { - if (stackA[length] == a) { - return stackB[length] == b; + result.length += valLength; + while (++valIndex < valLength) { + result[resIndex++] = value[valIndex]; + } + } else if (!isArgArrays) { + result.push(value); + } } + return result; } - var index = -1, - result = true, - size = 0; - - // add `a` and `b` to the stack of traversed objects - stackA.push(a); - stackB.push(b); + /** + * The base implementation of `_.isEqual`, without support for `thisArg` binding, + * that allows partial "_.where" style comparisons. + * + * @private + * @param {*} a The value to compare. + * @param {*} b The other value to compare. + * @param {Function} [callback] The function to customize comparing values. + * @param {Function} [isWhere=false] A flag to indicate performing partial comparisons. + * @param {Array} [stackA=[]] Tracks traversed `a` objects. + * @param {Array} [stackB=[]] Tracks traversed `b` objects. + * @returns {boolean} Returns `true` if the values are equivalent, else `false`. + */ + function baseIsEqual(a, b, callback, isWhere, stackA, stackB) { + // used to indicate that when comparing objects, `a` has at least the properties of `b` + if (callback) { + var result = callback(a, b); + if (typeof result != 'undefined') { + return !!result; + } + } + // exit early for identical values + if (a === b) { + // treat `+0` vs. `-0` as not equal + return a !== 0 || (1 / a == 1 / b); + } + var type = typeof a, + otherType = typeof b; - // recursively compare objects and arrays (susceptible to call stack limits) - if (isArr) { - // compare lengths to determine if a deep comparison is necessary - size = a.length; - result = size == b.length; + // exit early for unlike primitive values + if (a === a && + !(a && objectTypes[type]) && + !(b && objectTypes[otherType])) { + return false; + } + // exit early for `null` and `undefined` avoiding ES3's Function#call behavior + // http://es5.github.io/#x15.3.4.4 + if (a == null || b == null) { + return a === b; + } + // compare [[Class]] names + var className = toString.call(a), + otherClass = toString.call(b); - if (result) { + if (className == argsClass) { + className = objectClass; + } + if (otherClass == argsClass) { + otherClass = objectClass; + } + if (className != otherClass) { + return false; + } + switch (className) { + case boolClass: + case dateClass: + // coerce dates and booleans to numbers, dates to milliseconds and booleans + // to `1` or `0` treating invalid dates coerced to `NaN` as not equal + return +a == +b; + + case numberClass: + // treat `NaN` vs. `NaN` as equal + return (a != +a) + ? b != +b + // but treat `+0` vs. `-0` as not equal + : (a == 0 ? (1 / a == 1 / b) : a == +b); + + case regexpClass: + case stringClass: + // coerce regexes to strings (http://es5.github.io/#x15.10.6.4) + // treat string primitives and their corresponding object instances as equal + return a == String(b); + } + var isArr = className == arrayClass; + if (!isArr) { + // unwrap any `lodash` wrapped values + if (hasOwnProperty.call(a, '__wrapped__ ') || hasOwnProperty.call(b, '__wrapped__')) { + return baseIsEqual(a.__wrapped__ || a, b.__wrapped__ || b, callback, isWhere, stackA, stackB); + } + // exit for functions and DOM nodes + if (className != objectClass || (!support.nodeClass && (isNode(a) || isNode(b)))) { + return false; + } + // in older versions of Opera, `arguments` objects have `Array` constructors + var ctorA = !support.argsObject && isArguments(a) ? Object : a.constructor, + ctorB = !support.argsObject && isArguments(b) ? Object : b.constructor; + + // non `Object` object instances with different constructors are not equal + if (ctorA != ctorB && !( + isFunction(ctorA) && ctorA instanceof ctorA && + isFunction(ctorB) && ctorB instanceof ctorB + )) { + return false; + } + } + // assume cyclic structures are equal + // the algorithm for detecting cyclic structures is adapted from ES 5.1 + // section 15.12.3, abstract operation `JO` (http://es5.github.io/#x15.12.3) + var initedStack = !stackA; + stackA || (stackA = getArray()); + stackB || (stackB = getArray()); + + var length = stackA.length; + while (length--) { + if (stackA[length] == a) { + return stackB[length] == b; + } + } + var size = 0; + result = true; + + // add `a` and `b` to the stack of traversed objects + stackA.push(a); + stackB.push(b); + + // recursively compare objects and arrays (susceptible to call stack limits) + if (isArr) { + length = a.length; + size = b.length; + + // compare lengths to determine if a deep comparison is necessary + result = size == a.length; + if (!result && !isWhere) { + return result; + } // deep compare the contents, ignoring non-numeric properties while (size--) { - if (!(result = isEqual(a[size], b[size], data))) { + var index = length, + value = b[size]; + + if (isWhere) { + while (index--) { + if ((result = baseIsEqual(a[index], value, callback, isWhere, stackA, stackB))) { + break; + } + } + } else if (!(result = baseIsEqual(a[size], value, callback, isWhere, stackA, stackB))) { break; } } + return result; + } + // deep compare objects using `forIn`, instead of `forOwn`, to avoid `Object.keys` + // which, in this case, is more costly + forIn(b, function(value, key, b) { + if (hasOwnProperty.call(b, key)) { + // count the number of properties. + size++; + // deep compare each property value. + return (result = hasOwnProperty.call(a, key) && baseIsEqual(a[key], value, callback, isWhere, stackA, stackB)); + } + }); + + if (result && !isWhere) { + // ensure both objects have the same number of properties + forIn(a, function(value, key, a) { + if (hasOwnProperty.call(a, key)) { + // `size` will be `-1` if `a` has more properties than `b` + return (result = --size > -1); + } + }); + } + if (initedStack) { + releaseArray(stackA); + releaseArray(stackB); } return result; } - var ctorA = a.constructor, - ctorB = b.constructor; - - // non `Object` object instances with different constructors are not equal - if (ctorA != ctorB && !( - isFunction(ctorA) && ctorA instanceof ctorA && - isFunction(ctorB) && ctorB instanceof ctorB - )) { - return false; - } - // deep compare objects - for (var prop in a) { - if (hasOwnProperty.call(a, prop)) { - // count the number of properties. - size++; - // deep compare each property value. - if (!(hasOwnProperty.call(b, prop) && isEqual(a[prop], b[prop], data))) { - return false; + /** + * The base implementation of `_.merge` without argument juggling or support + * for `thisArg` binding. + * + * @private + * @param {Object} object The destination object. + * @param {Object} source The source object. + * @param {Function} [callback] The function to customize merging properties. + * @param {Array} [stackA=[]] Tracks traversed source objects. + * @param {Array} [stackB=[]] Associates values with source counterparts. + */ + function baseMerge(object, source, callback, stackA, stackB) { + (isArray(source) ? forEach : forOwn)(source, function(source, key) { + var found, + isArr, + result = source, + value = object[key]; + + if (source && ((isArr = isArray(source)) || isPlainObject(source))) { + // avoid merging previously merged cyclic sources + var stackLength = stackA.length; + while (stackLength--) { + if ((found = stackA[stackLength] == source)) { + value = stackB[stackLength]; + break; + } + } + if (!found) { + var isShallow; + if (callback) { + result = callback(value, source); + if ((isShallow = typeof result != 'undefined')) { + value = result; + } + } + if (!isShallow) { + value = isArr + ? (isArray(value) ? value : []) + : (isPlainObject(value) ? value : {}); + } + // add `source` and associated `value` to the stack of traversed objects + stackA.push(source); + stackB.push(value); + + // recursively merge objects and arrays (susceptible to call stack limits) + if (!isShallow) { + baseMerge(value, source, callback, stackA, stackB); + } + } } - } - } - // ensure both objects have the same number of properties - for (prop in b) { - // The JS engine in Adobe products, like InDesign, has a bug that causes - // `!size--` to throw an error so it must be wrapped in parentheses. - // https://github.com/documentcloud/underscore/issues/355 - if (hasOwnProperty.call(b, prop) && !(size--)) { - // `size` will be `-1` if `b` has more properties than `a` - return false; - } - } - // handle JScript [[DontEnum]] bug - if (hasDontEnumBug) { - while (++index < 7) { - prop = shadowed[index]; - if (hasOwnProperty.call(a, prop) && - !(hasOwnProperty.call(b, prop) && isEqual(a[prop], b[prop], data))) { - return false; + else { + if (callback) { + result = callback(value, source); + if (typeof result == 'undefined') { + result = source; + } + } + if (typeof result != 'undefined') { + value = result; + } } - } + object[key] = value; + }); } - return true; - } - /** - * Checks if `value` is a finite number. - * - * Note: This is not the same as native `isFinite`, which will return true for - * booleans and other values. See http://es5.github.com/#x15.1.2.5. - * - * @deprecated - * @static - * @memberOf _ - * @category Objects - * @param {Mixed} value The value to check. - * @returns {Boolean} Returns `true` if the `value` is a finite number, else `false`. - * @example - * - * _.isFinite(-101); - * // => true - * - * _.isFinite('10'); - * // => false - * - * _.isFinite(Infinity); - * // => false - */ - function isFinite(value) { - return nativeIsFinite(value) && toString.call(value) == numberClass; - } - - /** - * Checks if `value` is the language type of Object. - * (e.g. arrays, functions, objects, regexes, `new Number(0)`, and `new String('')`) - * - * @static - * @memberOf _ - * @category Objects - * @param {Mixed} value The value to check. - * @returns {Boolean} Returns `true` if the `value` is an object, else `false`. - * @example - * - * _.isObject({}); - * // => true - * - * _.isObject(1); - * // => false - */ - function isObject(value) { - // check if the value is the ECMAScript language type of Object - // http://es5.github.com/#x8 - // and avoid a V8 bug - // http://code.google.com/p/v8/issues/detail?id=2291 - return value ? objectTypes[typeof value] : false; - } + /** + * The base implementation of `_.uniq` without support for callback shorthands + * or `thisArg` binding. + * + * @private + * @param {Array} array The array to process. + * @param {boolean} [isSorted=false] A flag to indicate that `array` is sorted. + * @param {Function} [callback] The function called per iteration. + * @returns {Array} Returns a duplicate-value-free array. + */ + function baseUniq(array, isSorted, callback) { + var index = -1, + indexOf = getIndexOf(), + length = array ? array.length : 0, + result = []; - /** - * Checks if `value` is `NaN`. - * - * Note: This is not the same as native `isNaN`, which will return true for - * `undefined` and other values. See http://es5.github.com/#x15.1.2.4. - * - * @deprecated - * @static - * @memberOf _ - * @category Objects - * @param {Mixed} value The value to check. - * @returns {Boolean} Returns `true` if the `value` is `NaN`, else `false`. - * @example - * - * _.isNaN(NaN); - * // => true - * - * _.isNaN(new Number(NaN)); - * // => true - * - * isNaN(undefined); - * // => true - * - * _.isNaN(undefined); - * // => false - */ - function isNaN(value) { - // `NaN` as a primitive is the only value that is not equal to itself - // (perform the [[Class]] check first to avoid errors with some host objects in IE) - return toString.call(value) == numberClass && value != +value - } + var isLarge = !isSorted && length >= largeArraySize && indexOf === baseIndexOf, + seen = (callback || isLarge) ? getArray() : result; - /** - * Checks if `value` is `null`. - * - * @deprecated - * @static - * @memberOf _ - * @category Objects - * @param {Mixed} value The value to check. - * @returns {Boolean} Returns `true` if the `value` is `null`, else `false`. - * @example - * - * _.isNull(null); - * // => true - * - * _.isNull(undefined); - * // => false - */ - function isNull(value) { - return value === null; - } + if (isLarge) { + var cache = createCache(seen); + if (cache) { + indexOf = cacheIndexOf; + seen = cache; + } else { + isLarge = false; + seen = callback ? seen : (releaseArray(seen), result); + } + } + while (++index < length) { + var value = array[index], + computed = callback ? callback(value, index, array) : value; + + if (isSorted + ? !index || seen[seen.length - 1] !== computed + : indexOf(seen, computed) < 0 + ) { + if (callback || isLarge) { + seen.push(computed); + } + result.push(value); + } + } + if (isLarge) { + releaseArray(seen.array); + releaseObject(seen); + } else if (callback) { + releaseArray(seen); + } + return result; + } - /** - * Checks if `value` is a number. - * - * @static - * @memberOf _ - * @category Objects - * @param {Mixed} value The value to check. - * @returns {Boolean} Returns `true` if the `value` is a number, else `false`. - * @example - * - * _.isNumber(8.4 * 5; - * // => true - */ - function isNumber(value) { - return toString.call(value) == numberClass; - } + /** + * Creates a function that aggregates a collection, creating an object composed + * of keys generated from the results of running each element of the collection + * through a callback. The given `setter` function sets the keys and values + * of the composed object. + * + * @private + * @param {Function} setter The setter function. + * @returns {Function} Returns the new aggregator function. + */ + function createAggregator(setter) { + return function(collection, callback, thisArg) { + var result = {}; + callback = lodash.createCallback(callback, thisArg, 3); + + if (isArray(collection)) { + var index = -1, + length = collection.length; + + while (++index < length) { + var value = collection[index]; + setter(result, value, callback(value, index, collection), collection); + } + } else { + baseEach(collection, function(value, key, collection) { + setter(result, value, callback(value, key, collection), collection); + }); + } + return result; + }; + } - /** - * Checks if `value` is a regular expression. - * - * @static - * @memberOf _ - * @category Objects - * @param {Mixed} value The value to check. - * @returns {Boolean} Returns `true` if the `value` is a regular expression, else `false`. - * @example - * - * _.isRegExp(/moe/); - * // => true - */ - function isRegExp(value) { - return toString.call(value) == regexpClass; - } + /** + * Creates a function that, when called, either curries or invokes `func` + * with an optional `this` binding and partially applied arguments. + * + * @private + * @param {Function|string} func The function or method name to reference. + * @param {number} bitmask The bitmask of method flags to compose. + * The bitmask may be composed of the following flags: + * 1 - `_.bind` + * 2 - `_.bindKey` + * 4 - `_.curry` + * 8 - `_.curry` (bound) + * 16 - `_.partial` + * 32 - `_.partialRight` + * @param {Array} [partialArgs] An array of arguments to prepend to those + * provided to the new function. + * @param {Array} [partialRightArgs] An array of arguments to append to those + * provided to the new function. + * @param {*} [thisArg] The `this` binding of `func`. + * @param {number} [arity] The arity of `func`. + * @returns {Function} Returns the new bound function. + */ + function createBound(func, bitmask, partialArgs, partialRightArgs, thisArg, arity) { + var isBind = bitmask & 1, + isBindKey = bitmask & 2, + isCurry = bitmask & 4, + isCurryBound = bitmask & 8, + isPartial = bitmask & 16, + isPartialRight = bitmask & 32, + key = func; + + if (!isBindKey && !isFunction(func)) { + throw new TypeError; + } + if (isPartial && !partialArgs.length) { + bitmask &= ~16; + isPartial = partialArgs = false; + } + if (isPartialRight && !partialRightArgs.length) { + bitmask &= ~32; + isPartialRight = partialRightArgs = false; + } + var bindData = func && func.__bindData__; + if (bindData) { + if (isBind && !(bindData[1] & 1)) { + bindData[4] = thisArg; + } + if (!isBind && bindData[1] & 1) { + bitmask |= 8; + } + if (isCurry && !(bindData[1] & 4)) { + bindData[5] = arity; + } + if (isPartial) { + push.apply(bindData[2] || (bindData[2] = []), partialArgs); + } + if (isPartialRight) { + push.apply(bindData[3] || (bindData[3] = []), partialRightArgs); + } + bindData[1] |= bitmask; + return createBound.apply(null, bindData); + } + // use `Function#bind` if it exists and is fast + // (in V8 `Function#bind` is slower except when partially applied) + if (isBind && !(isBindKey || isCurry || isPartialRight) && + (support.fastBind || (nativeBind && isPartial))) { + if (isPartial) { + var args = [thisArg]; + push.apply(args, partialArgs); + } + var bound = isPartial + ? nativeBind.apply(func, args) + : nativeBind.call(func, thisArg); + } + else { + bound = function() { + // `Function#bind` spec + // http://es5.github.io/#x15.3.4.5 + var args = arguments, + thisBinding = isBind ? thisArg : this; + + if (isCurry || isPartial || isPartialRight) { + args = nativeSlice.call(args); + if (isPartial) { + unshift.apply(args, partialArgs); + } + if (isPartialRight) { + push.apply(args, partialRightArgs); + } + if (isCurry && args.length < arity) { + bitmask |= 16 & ~32; + return createBound(func, (isCurryBound ? bitmask : bitmask & ~3), args, null, thisArg, arity); + } + } + if (isBindKey) { + func = thisBinding[key]; + } + if (this instanceof bound) { + // ensure `new bound` is an instance of `func` + thisBinding = createObject(func.prototype); + + // mimic the constructor's `return` behavior + // http://es5.github.io/#x13.2.2 + var result = func.apply(thisBinding, args); + return isObject(result) ? result : thisBinding; + } + return func.apply(thisBinding, args); + }; + } + setBindData(bound, nativeSlice.call(arguments)); + return bound; + } - /** - * Checks if `value` is a string. - * - * @static - * @memberOf _ - * @category Objects - * @param {Mixed} value The value to check. - * @returns {Boolean} Returns `true` if the `value` is a string, else `false`. - * @example - * - * _.isString('moe'); - * // => true - */ - function isString(value) { - return toString.call(value) == stringClass; - } + /** + * Creates compiled iteration functions. + * + * @private + * @param {...Object} [options] The compile options object(s). + * @param {string} [options.array] Code to determine if the iterable is an array or array-like. + * @param {boolean} [options.useHas] Specify using `hasOwnProperty` checks in the object loop. + * @param {Function} [options.keys] A reference to `_.keys` for use in own property iteration. + * @param {string} [options.args] A comma separated string of iteration function arguments. + * @param {string} [options.top] Code to execute before the iteration branches. + * @param {string} [options.loop] Code to execute in the object loop. + * @param {string} [options.bottom] Code to execute after the iteration branches. + * @returns {Function} Returns the compiled function. + */ + function createIterator() { + // data properties + iteratorData.shadowedProps = shadowedProps; + + // iterator options + iteratorData.array = iteratorData.bottom = iteratorData.loop = iteratorData.top = ''; + iteratorData.init = 'iterable'; + iteratorData.useHas = true; + + // merge options into a template data object + for (var object, index = 0; object = arguments[index]; index++) { + for (var key in object) { + iteratorData[key] = object[key]; + } + } + var args = iteratorData.args; + iteratorData.firstArg = /^[^,]+/.exec(args)[0]; + + // create the function factory + var factory = Function( + 'baseCreateCallback, errorClass, errorProto, hasOwnProperty, ' + + 'indicatorObject, isArguments, isArray, isString, keys, objectProto, ' + + 'objectTypes, nonEnumProps, stringClass, stringProto, toString', + 'return function(' + args + ') {\n' + iteratorTemplate(iteratorData) + '\n}' + ); + + // return the compiled function + return factory( + baseCreateCallback, errorClass, errorProto, hasOwnProperty, + indicatorObject, isArguments, isArray, isString, iteratorData.keys, objectProto, + objectTypes, nonEnumProps, stringClass, stringProto, toString + ); + } - /** - * Checks if `value` is `undefined`. - * - * @deprecated - * @static - * @memberOf _ - * @category Objects - * @param {Mixed} value The value to check. - * @returns {Boolean} Returns `true` if the `value` is `undefined`, else `false`. - * @example - * - * _.isUndefined(void 0); - * // => true - */ - function isUndefined(value) { - return value === undefined; - } + /** + * Creates a new object with the specified `prototype`. + * + * @private + * @param {Object} prototype The prototype object. + * @returns {Object} Returns the new object. + */ + function createObject(prototype) { + return isObject(prototype) ? nativeCreate(prototype) : {}; + } + // fallback for browsers without `Object.create` + if (!nativeCreate) { + createObject = function(prototype) { + if (isObject(prototype)) { + noop.prototype = prototype; + var result = new noop; + noop.prototype = null; + } + return result || {}; + }; + } - /** - * Creates an array composed of the own enumerable property names of `object`. - * - * @static - * @memberOf _ - * @category Objects - * @param {Object} object The object to inspect. - * @returns {Array} Returns a new array of property names. - * @example - * - * _.keys({ 'one': 1, 'two': 2, 'three': 3 }); - * // => ['one', 'two', 'three'] (order is not guaranteed) - */ - var keys = !nativeKeys ? shimKeys : function(object) { - var type = typeof object; + /** + * Used by `escape` to convert characters to HTML entities. + * + * @private + * @param {string} match The matched character to escape. + * @returns {string} Returns the escaped character. + */ + function escapeHtmlChar(match) { + return htmlEscapes[match]; + } - // avoid iterating over the `prototype` property - if (type == 'function' && propertyIsEnumerable.call(object, 'prototype')) { - return shimKeys(object); + /** + * Gets the appropriate "indexOf" function. If the `_.indexOf` method is + * customized, this method returns the custom method, otherwise it returns + * the `baseIndexOf` function. + * + * @private + * @returns {Function} Returns the "indexOf" function. + */ + function getIndexOf() { + var result = (result = lodash.indexOf) === indexOf ? baseIndexOf : result; + return result; } - return object && objectTypes[type] - ? nativeKeys(object) - : []; - }; - /** - * Merges enumerable properties of the source object(s) into the `destination` - * object. Subsequent sources will overwrite propery assignments of previous - * sources. - * - * @static - * @memberOf _ - * @category Objects - * @param {Object} object The destination object. - * @param {Object} [source1, source2, ...] The source objects. - * @param {Object} [indicator] Internally used to indicate that the `stack` - * argument is an array of traversed objects instead of another source object. - * @param {Object} [data={}] Internally used to track traversed objects to avoid - * circular references. - * @returns {Object} Returns the destination object. - * @example - * - * var stooges = [ - * { 'name': 'moe' }, - * { 'name': 'larry' } - * ]; - * - * var ages = [ - * { 'age': 40 }, - * { 'age': 50 } - * ]; - * - * _.merge(stooges, ages); - * // => [{ 'name': 'moe', 'age': 40 }, { 'name': 'larry', 'age': 50 }] - */ - var merge = createIterator(extendIteratorOptions, { - 'args': 'object, source, indicator', - 'top': - 'var isArr, recursive = indicator == isPlainObject,\n' + - ' data = recursive ? arguments[3] : { values: [], sources: [] };\n' + - 'for (var argsIndex = 1, argsLength = recursive ? 2 : arguments.length; argsIndex < argsLength; argsIndex++) {\n' + - ' if (iteratee = arguments[argsIndex]) {', - 'inLoop': - 'if ((source = value) && ((isArr = isArray(source)) || isPlainObject(source))) {\n' + - ' var found = false, values = data.values, sources = data.sources, stackLength = sources.length;\n' + - ' while (stackLength--) {\n' + - ' if (found = sources[stackLength] == source) break\n' + - ' }\n' + - ' if (found) {\n' + - ' result[index] = values[stackLength]\n' + - ' } else {\n' + - ' values.push(value = (value = result[index]) && isArr\n' + - ' ? (isArray(value) ? value : [])\n' + - ' : (isPlainObject(value) ? value : {})\n' + - ' );\n' + - ' sources.push(source);\n' + - ' result[index] = callee(value, source, isPlainObject, data)\n' + - ' }\n' + - '} else if (source != null) {\n' + - ' result[index] = source\n' + - '}' - }); + /** + * Sets `this` binding data on a given function. + * + * @private + * @param {Function} func The function to set data on. + * @param {*} value The value to set. + */ + var setBindData = !defineProperty ? noop : function(func, value) { + descriptor.value = value; + defineProperty(func, '__bindData__', descriptor); + }; - /** - * Creates a shallow clone of `object` excluding the specified properties. - * Property names may be specified as individual arguments or as arrays of - * property names. If `callback` is passed, it will be executed for each property - * in the `object`, omitting the properties `callback` returns truthy for. The - * `callback` is bound to `thisArg` and invoked with 3 arguments; (value, key, object). - * - * @static - * @memberOf _ - * @category Objects - * @param {Object} object The source object. - * @param {Function|String} callback|[prop1, prop2, ...] The properties to omit - * or the function called per iteration. - * @param {Mixed} [thisArg] The `this` binding for the callback. - * @returns {Object} Returns an object without the omitted properties. - * @example - * - * _.omit({ 'name': 'moe', 'age': 40, 'userid': 'moe1' }, 'userid'); - * // => { 'name': 'moe', 'age': 40 } - * - * _.omit({ 'name': 'moe', '_hint': 'knucklehead', '_seed': '96c4eb' }, function(value, key) { - * return key.charAt(0) == '_'; - * }); - * // => { 'name': 'moe' } - */ - var omit = createIterator(omitIteratorOptions); + /** + * A fallback implementation of `isPlainObject` which checks if a given value + * is an object created by the `Object` constructor, assuming objects created + * by the `Object` constructor have no inherited enumerable properties and that + * there are no `Object.prototype` extensions. + * + * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a plain object, else `false`. + */ + function shimIsPlainObject(value) { + var ctor, + result; + + // avoid non Object objects, `arguments` objects, and DOM elements + if (!(value && toString.call(value) == objectClass) || + (ctor = value.constructor, isFunction(ctor) && !(ctor instanceof ctor)) || + (!support.argsClass && isArguments(value)) || + (!support.nodeClass && isNode(value))) { + return false; + } + // IE < 9 iterates inherited properties before own properties. If the first + // iterated property is an object's own property then there are no inherited + // enumerable properties. + if (support.ownLast) { + forIn(value, function(value, key, object) { + result = hasOwnProperty.call(object, key); + return false; + }); + return result !== false; + } + // In most environments an object's own properties are iterated before + // its inherited properties. If the last iterated property is an object's + // own property then there are no inherited enumerable properties. + forIn(value, function(value, key) { + result = key; + }); + return typeof result == 'undefined' || hasOwnProperty.call(value, result); + } - /** - * Creates a two dimensional array of the given object's key-value pairs, - * i.e. `[[key1, value1], [key2, value2]]`. - * - * @static - * @memberOf _ - * @category Objects - * @param {Object} object The object to inspect. - * @returns {Array} Returns new array of key-value pairs. - * @example - * - * _.pairs({ 'moe': 30, 'larry': 40, 'curly': 50 }); - * // => [['moe', 30], ['larry', 40], ['curly', 50]] (order is not guaranteed) - */ - var pairs = createIterator({ - 'args': 'object', - 'init':'[]', - 'inLoop': 'result' + (isKeysFast ? '[ownIndex] = ' : '.push') + '([index, value])' - }); + /** + * Used by `unescape` to convert HTML entities to characters. + * + * @private + * @param {string} match The matched character to unescape. + * @returns {string} Returns the unescaped character. + */ + function unescapeHtmlChar(match) { + return htmlUnescapes[match]; + } - /** - * Creates a shallow clone of `object` composed of the specified properties. - * Property names may be specified as individual arguments or as arrays of - * property names. If `callback` is passed, it will be executed for each property - * in the `object`, picking the properties `callback` returns truthy for. The - * `callback` is bound to `thisArg` and invoked with 3 arguments; (value, key, object). - * - * @static - * @memberOf _ - * @category Objects - * @param {Object} object The source object. - * @param {Function|String} callback|[prop1, prop2, ...] The properties to pick - * or the function called per iteration. - * @param {Mixed} [thisArg] The `this` binding for the callback. - * @returns {Object} Returns an object composed of the picked properties. - * @example - * - * _.pick({ 'name': 'moe', 'age': 40, 'userid': 'moe1' }, 'name', 'age'); - * // => { 'name': 'moe', 'age': 40 } - * - * _.pick({ 'name': 'moe', '_hint': 'knucklehead', '_seed': '96c4eb' }, function(value, key) { - * return key.charAt(0) != '_'; - * }); - * // => { 'name': 'moe' } - */ - var pick = createIterator(omitIteratorOptions, { - 'top': - 'if (typeof callback != \'function\') {\n' + - ' var prop,\n' + - ' props = concat.apply(ArrayProto, arguments),\n' + - ' length = props.length;\n' + - ' for (index = 1; index < length; index++) {\n' + - ' prop = props[index];\n' + - ' if (prop in object) result[prop] = object[prop]\n' + - ' }\n' + - '} else {\n' + - ' if (thisArg) callback = iteratorBind(callback, thisArg)', - 'inLoop': - 'if (callback(value, index, object)) result[index] = value', - 'bottom': '}' - }); + /*--------------------------------------------------------------------------*/ - /** - * Creates an array composed of the own enumerable property values of `object`. - * - * @static - * @memberOf _ - * @category Objects - * @param {Object} object The object to inspect. - * @returns {Array} Returns a new array of property values. - * @example - * - * _.values({ 'one': 1, 'two': 2, 'three': 3 }); - * // => [1, 2, 3] - */ - var values = createIterator({ - 'args': 'object', - 'init': '[]', - 'inLoop': 'result.push(value)' - }); + /** + * Checks if `value` is an `arguments` object. + * + * @static + * @memberOf _ + * @category Objects + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if the `value` is an `arguments` object, else `false`. + * @example + * + * (function() { return _.isArguments(arguments); })(1, 2, 3); + * // => true + * + * _.isArguments([1, 2, 3]); + * // => false + */ + function isArguments(value) { + return value && typeof value == 'object' && typeof value.length == 'number' && + toString.call(value) == argsClass || false; + } + // fallback for browsers that can't detect `arguments` objects by [[Class]] + if (!support.argsClass) { + isArguments = function(value) { + return value && typeof value == 'object' && typeof value.length == 'number' && + hasOwnProperty.call(value, 'callee') || false; + }; + } - /*--------------------------------------------------------------------------*/ + /** + * Checks if `value` is an array. + * + * @static + * @memberOf _ + * @type Function + * @category Objects + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if the `value` is an array, else `false`. + * @example + * + * (function() { return _.isArray(arguments); })(); + * // => false + * + * _.isArray([1, 2, 3]); + * // => true + */ + var isArray = nativeIsArray || function(value) { + return value && typeof value == 'object' && typeof value.length == 'number' && + toString.call(value) == arrayClass || false; + }; - /** - * Checks if a given `target` element is present in a `collection` using strict - * equality for comparisons, i.e. `===`. - * - * @static - * @memberOf _ - * @alias include - * @category Collections - * @param {Array|Object|String} collection The collection to iterate over. - * @param {Mixed} target The value to check for. - * @returns {Boolean} Returns `true` if the `target` element is found, else `false`. - * @example - * - * _.contains([1, 2, 3], 3); - * // => true - * - * _.contains({ 'name': 'moe', 'age': 40 }, 'moe'); - * // => true - * - * _.contains('curly', 'ur'); - * // => true - */ - var contains = createIterator({ - 'args': 'collection, target', - 'init': 'false', - 'noCharByIndex': false, - 'beforeLoop': { - 'array': 'if (toString.call(collection) == stringClass) return collection.indexOf(target) > -1' - }, - 'inLoop': 'if (value === target) return true' - }); + /** + * A fallback implementation of `Object.keys` which produces an array of the + * given object's own enumerable property names. + * + * @private + * @type Function + * @param {Object} object The object to inspect. + * @returns {Array} Returns an array of property names. + */ + var shimKeys = createIterator({ + 'args': 'object', + 'init': '[]', + 'top': 'if (!(objectTypes[typeof object])) return result', + 'loop': 'result.push(index)' + }); - /** - * Creates an object composed of keys returned from running each element of - * `collection` through a `callback`. The corresponding value of each key is - * the number of times the key was returned by `callback`. The `callback` is - * bound to `thisArg` and invoked with 3 arguments; (value, index|key, collection). - * The `callback` argument may also be the name of a property to count by (e.g. 'length'). - * - * @static - * @memberOf _ - * @category Collections - * @param {Array|Object|String} collection The collection to iterate over. - * @param {Function|String} callback|property The function called per iteration - * or property name to count by. - * @param {Mixed} [thisArg] The `this` binding for the callback. - * @returns {Object} Returns the composed aggregate object. - * @example - * - * _.countBy([4.3, 6.1, 6.4], function(num) { return Math.floor(num); }); - * // => { '4': 1, '6': 2 } - * - * _.countBy([4.3, 6.1, 6.4], function(num) { return this.floor(num); }, Math); - * // => { '4': 1, '6': 2 } - * - * _.countBy(['one', 'two', 'three'], 'length'); - * // => { '3': 2, '5': 1 } - */ - var countBy = createIterator(baseIteratorOptions, countByIteratorOptions); + /** + * Creates an array composed of the own enumerable property names of an object. + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The object to inspect. + * @returns {Array} Returns an array of property names. + * @example + * + * _.keys({ 'one': 1, 'two': 2, 'three': 3 }); + * // => ['one', 'two', 'three'] (property order is not guaranteed across environments) + */ + var keys = !nativeKeys ? shimKeys : function(object) { + if (!isObject(object)) { + return []; + } + if ((support.enumPrototypes && typeof object == 'function') || + (support.nonEnumArgs && object.length && isArguments(object))) { + return shimKeys(object); + } + return nativeKeys(object); + }; - /** - * Checks if the `callback` returns a truthy value for **all** elements of a - * `collection`. The `callback` is bound to `thisArg` and invoked with 3 - * arguments; (value, index|key, collection). - * - * @static - * @memberOf _ - * @alias all - * @category Collections - * @param {Array|Object|String} collection The collection to iterate over. - * @param {Function} [callback=identity] The function called per iteration. - * @param {Mixed} [thisArg] The `this` binding for the callback. - * @returns {Boolean} Returns `true` if all elements pass the callback check, else `false`. - * @example - * - * _.every([true, 1, null, 'yes'], Boolean); - * // => false - */ - var every = createIterator(baseIteratorOptions, everyIteratorOptions); + /** Reusable iterator options shared by `each`, `forIn`, and `forOwn` */ + var eachIteratorOptions = { + 'args': 'collection, callback, thisArg', + 'top': "callback = callback && typeof thisArg == 'undefined' ? callback : baseCreateCallback(callback, thisArg, 3)", + 'array': "typeof length == 'number'", + 'keys': keys, + 'loop': 'if (callback(iterable[index], index, collection) === false) return result' + }; - /** - * Examines each element in a `collection`, returning an array of all elements - * the `callback` returns truthy for. The `callback` is bound to `thisArg` and - * invoked with 3 arguments; (value, index|key, collection). - * - * @static - * @memberOf _ - * @alias select - * @category Collections - * @param {Array|Object|String} collection The collection to iterate over. - * @param {Function} [callback=identity] The function called per iteration. - * @param {Mixed} [thisArg] The `this` binding for the callback. - * @returns {Array} Returns a new array of elements that passed callback check. - * @example - * - * var evens = _.filter([1, 2, 3, 4, 5, 6], function(num) { return num % 2 == 0; }); - * // => [2, 4, 6] - */ - var filter = createIterator(baseIteratorOptions, filterIteratorOptions); + /** Reusable iterator options for `assign` and `defaults` */ + var defaultsIteratorOptions = { + 'args': 'object, source, guard', + 'top': + 'var args = arguments,\n' + + ' argsIndex = 0,\n' + + " argsLength = typeof guard == 'number' ? 2 : args.length;\n" + + 'while (++argsIndex < argsLength) {\n' + + ' iterable = args[argsIndex];\n' + + ' if (iterable && objectTypes[typeof iterable]) {', + 'keys': keys, + 'loop': "if (typeof result[index] == 'undefined') result[index] = iterable[index]", + 'bottom': ' }\n}' + }; - /** - * Examines each element in a `collection`, returning the first one the `callback` - * returns truthy for. The function returns as soon as it finds an acceptable - * element, and does not iterate over the entire `collection`. The `callback` is - * bound to `thisArg` and invoked with 3 arguments; (value, index|key, collection). - * - * @static - * @memberOf _ - * @alias detect - * @category Collections - * @param {Array|Object|String} collection The collection to iterate over. - * @param {Function} callback The function called per iteration. - * @param {Mixed} [thisArg] The `this` binding for the callback. - * @returns {Mixed} Returns the element that passed the callback check, else `undefined`. - * @example - * - * var even = _.find([1, 2, 3, 4, 5, 6], function(num) { return num % 2 == 0; }); - * // => 2 - */ - var find = createIterator(baseIteratorOptions, forEachIteratorOptions, { - 'init': '', - 'inLoop': 'if (callback(value, index, collection)) return value' - }); + /** Reusable iterator options for `forIn` and `forOwn` */ + var forOwnIteratorOptions = { + 'top': 'if (!objectTypes[typeof iterable]) return result;\n' + eachIteratorOptions.top, + 'array': false + }; + + /** + * Used to convert characters to HTML entities: + * + * Though the `>` character is escaped for symmetry, characters like `>` and `/` + * don't require escaping in HTML and have no special meaning unless they're part + * of a tag or an unquoted attribute value. + * http://mathiasbynens.be/notes/ambiguous-ampersands (under "semi-related fun fact") + */ + var htmlEscapes = { + '&': '&', + '<': '<', + '>': '>', + '"': '"', + "'": ''' + }; + + /** Used to convert HTML entities to characters */ + var htmlUnescapes = invert(htmlEscapes); + + /** Used to match HTML entities and HTML characters */ + var reEscapedHtml = RegExp('(' + keys(htmlUnescapes).join('|') + ')', 'g'), + reUnescapedHtml = RegExp('[' + keys(htmlEscapes).join('') + ']', 'g'); + + /** + * A function compiled to iterate `arguments` objects, arrays, objects, and + * strings consistenly across environments, executing the callback for each + * element in the collection. The callback is bound to `thisArg` and invoked + * with three arguments; (value, index|key, collection). Callbacks may exit + * iteration early by explicitly returning `false`. + * + * @private + * @type Function + * @param {Array|Object|string} collection The collection to iterate over. + * @param {Function} [callback=identity] The function called per iteration. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {Array|Object|string} Returns `collection`. + */ + var baseEach = createIterator(eachIteratorOptions); + + /*--------------------------------------------------------------------------*/ + + /** + * Assigns own enumerable properties of source object(s) to the destination + * object. Subsequent sources will overwrite property assignments of previous + * sources. If a callback is provided it will be executed to produce the + * assigned values. The callback is bound to `thisArg` and invoked with two + * arguments; (objectValue, sourceValue). + * + * @static + * @memberOf _ + * @type Function + * @alias extend + * @category Objects + * @param {Object} object The destination object. + * @param {...Object} [source] The source objects. + * @param {Function} [callback] The function to customize assigning values. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {Object} Returns the destination object. + * @example + * + * _.assign({ 'name': 'moe' }, { 'age': 40 }); + * // => { 'name': 'moe', 'age': 40 } + * + * var defaults = _.partialRight(_.assign, function(a, b) { + * return typeof a == 'undefined' ? b : a; + * }); + * + * var food = { 'name': 'apple' }; + * defaults(food, { 'name': 'banana', 'type': 'fruit' }); + * // => { 'name': 'apple', 'type': 'fruit' } + */ + var assign = createIterator(defaultsIteratorOptions, { + 'top': + defaultsIteratorOptions.top.replace(';', + ';\n' + + "if (argsLength > 3 && typeof args[argsLength - 2] == 'function') {\n" + + ' var callback = baseCreateCallback(args[--argsLength - 1], args[argsLength--], 2);\n' + + "} else if (argsLength > 2 && typeof args[argsLength - 1] == 'function') {\n" + + ' callback = args[--argsLength];\n' + + '}' + ), + 'loop': 'result[index] = callback ? callback(result[index], iterable[index]) : iterable[index]' + }); + + /** + * Creates a clone of `value`. If `deep` is `true` nested objects will also + * be cloned, otherwise they will be assigned by reference. If a callback + * is provided it will be executed to produce the cloned values. If the + * callback returns `undefined` cloning will be handled by the method instead. + * The callback is bound to `thisArg` and invoked with one argument; (value). + * + * @static + * @memberOf _ + * @category Objects + * @param {*} value The value to clone. + * @param {boolean} [deep=false] Specify a deep clone. + * @param {Function} [callback] The function to customize cloning values. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {*} Returns the cloned value. + * @example + * + * var stooges = [ + * { 'name': 'moe', 'age': 40 }, + * { 'name': 'larry', 'age': 50 } + * ]; + * + * var shallow = _.clone(stooges); + * shallow[0] === stooges[0]; + * // => true + * + * var deep = _.clone(stooges, true); + * deep[0] === stooges[0]; + * // => false + * + * _.mixin({ + * 'clone': _.partialRight(_.clone, function(value) { + * return _.isElement(value) ? value.cloneNode(false) : undefined; + * }) + * }); + * + * var clone = _.clone(document.body); + * clone.childNodes.length; + * // => 0 + */ + function clone(value, deep, callback, thisArg) { + // allows working with "Collections" methods without using their `index` + // and `collection` arguments for `deep` and `callback` + if (typeof deep != 'boolean' && deep != null) { + thisArg = callback; + callback = deep; + deep = false; + } + return baseClone(value, deep, typeof callback == 'function' && baseCreateCallback(callback, thisArg, 1)); + } + + /** + * Creates a deep clone of `value`. If a callback is provided it will be + * executed to produce the cloned values. If the callback returns `undefined` + * cloning will be handled by the method instead. The callback is bound to + * `thisArg` and invoked with one argument; (value). + * + * Note: This method is loosely based on the structured clone algorithm. Functions + * and DOM nodes are **not** cloned. The enumerable properties of `arguments` objects and + * objects created by constructors other than `Object` are cloned to plain `Object` objects. + * See http://www.w3.org/TR/html5/infrastructure.html#internal-structured-cloning-algorithm. + * + * @static + * @memberOf _ + * @category Objects + * @param {*} value The value to deep clone. + * @param {Function} [callback] The function to customize cloning values. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {*} Returns the deep cloned value. + * @example + * + * var stooges = [ + * { 'name': 'moe', 'age': 40 }, + * { 'name': 'larry', 'age': 50 } + * ]; + * + * var deep = _.cloneDeep(stooges); + * deep[0] === stooges[0]; + * // => false + * + * var view = { + * 'label': 'docs', + * 'node': element + * }; + * + * var clone = _.cloneDeep(view, function(value) { + * return _.isElement(value) ? value.cloneNode(true) : undefined; + * }); + * + * clone.node == view.node; + * // => false + */ + function cloneDeep(value, callback, thisArg) { + return baseClone(value, true, typeof callback == 'function' && baseCreateCallback(callback, thisArg, 1)); + } + + /** + * Assigns own enumerable properties of source object(s) to the destination + * object for all destination properties that resolve to `undefined`. Once a + * property is set, additional defaults of the same property will be ignored. + * + * @static + * @memberOf _ + * @type Function + * @category Objects + * @param {Object} object The destination object. + * @param {...Object} [source] The source objects. + * @param- {Object} [guard] Allows working with `_.reduce` without using its + * `key` and `object` arguments as sources. + * @returns {Object} Returns the destination object. + * @example + * + * var food = { 'name': 'apple' }; + * _.defaults(food, { 'name': 'banana', 'type': 'fruit' }); + * // => { 'name': 'apple', 'type': 'fruit' } + */ + var defaults = createIterator(defaultsIteratorOptions); + + /** + * This method is like `_.findIndex` except that it returns the key of the + * first element that passes the callback check, instead of the element itself. + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The object to search. + * @param {Function|Object|string} [callback=identity] The function called per + * iteration. If a property name or object is provided it will be used to + * create a "_.pluck" or "_.where" style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {string|undefined} Returns the key of the found element, else `undefined`. + * @example + * + * _.findKey({ 'a': 1, 'b': 2, 'c': 3, 'd': 4 }, function(num) { + * return num % 2 == 0; + * }); + * // => 'b' (property order is not guaranteed across environments) + */ + function findKey(object, callback, thisArg) { + var result; + callback = lodash.createCallback(callback, thisArg, 3); + forOwn(object, function(value, key, object) { + if (callback(value, key, object)) { + result = key; + return false; + } + }); + return result; + } + + /** + * This method is like `_.findKey` except that it iterates over elements + * of a `collection` in the opposite order. + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The object to search. + * @param {Function|Object|string} [callback=identity] The function called per + * iteration. If a property name or object is provided it will be used to + * create a "_.pluck" or "_.where" style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {string|undefined} Returns the key of the found element, else `undefined`. + * @example + * + * _.findLastKey({ 'a': 1, 'b': 2, 'c': 3, 'd': 4 }, function(num) { + * return num % 2 == 1; + * }); + * // => returns `c`, assuming `_.findKey` returns `a` + */ + function findLastKey(object, callback, thisArg) { + var result; + callback = lodash.createCallback(callback, thisArg, 3); + forOwnRight(object, function(value, key, object) { + if (callback(value, key, object)) { + result = key; + return false; + } + }); + return result; + } + + /** + * Iterates over own and inherited enumerable properties of an object, + * executing the callback for each property. The callback is bound to `thisArg` + * and invoked with three arguments; (value, key, object). Callbacks may exit + * iteration early by explicitly returning `false`. + * + * @static + * @memberOf _ + * @type Function + * @category Objects + * @param {Object} object The object to iterate over. + * @param {Function} [callback=identity] The function called per iteration. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {Object} Returns `object`. + * @example + * + * function Dog(name) { + * this.name = name; + * } + * + * Dog.prototype.bark = function() { + * console.log('Woof, woof!'); + * }; + * + * _.forIn(new Dog('Dagny'), function(value, key) { + * console.log(key); + * }); + * // => logs 'bark' and 'name' (property order is not guaranteed across environments) + */ + var forIn = createIterator(eachIteratorOptions, forOwnIteratorOptions, { + 'useHas': false + }); + + /** + * This method is like `_.forIn` except that it iterates over elements + * of a `collection` in the opposite order. + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The object to iterate over. + * @param {Function} [callback=identity] The function called per iteration. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {Object} Returns `object`. + * @example + * + * function Dog(name) { + * this.name = name; + * } + * + * Dog.prototype.bark = function() { + * console.log('Woof, woof!'); + * }; + * + * _.forInRight(new Dog('Dagny'), function(value, key) { + * console.log(key); + * }); + * // => logs 'name' and 'bark' assuming `_.forIn ` logs 'bark' and 'name' + */ + function forInRight(object, callback, thisArg) { + var pairs = []; + + forIn(object, function(value, key) { + pairs.push(key, value); + }); + + var length = pairs.length; + callback = baseCreateCallback(callback, thisArg, 3); + while (length--) { + if (callback(pairs[length--], pairs[length], object) === false) { + break; + } + } + return object; + } + + /** + * Iterates over own enumerable properties of an object, executing the callback + * for each property. The callback is bound to `thisArg` and invoked with three + * arguments; (value, key, object). Callbacks may exit iteration early by + * explicitly returning `false`. + * + * @static + * @memberOf _ + * @type Function + * @category Objects + * @param {Object} object The object to iterate over. + * @param {Function} [callback=identity] The function called per iteration. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {Object} Returns `object`. + * @example + * + * _.forOwn({ '0': 'zero', '1': 'one', 'length': 2 }, function(num, key) { + * console.log(key); + * }); + * // => logs '0', '1', and 'length' (property order is not guaranteed across environments) + */ + var forOwn = createIterator(eachIteratorOptions, forOwnIteratorOptions); + + /** + * This method is like `_.forOwn` except that it iterates over elements + * of a `collection` in the opposite order. + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The object to iterate over. + * @param {Function} [callback=identity] The function called per iteration. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {Object} Returns `object`. + * @example + * + * _.forOwnRight({ '0': 'zero', '1': 'one', 'length': 2 }, function(num, key) { + * console.log(key); + * }); + * // => logs 'length', '1', and '0' assuming `_.forOwn` logs '0', '1', and 'length' + */ + function forOwnRight(object, callback, thisArg) { + var props = keys(object), + length = props.length; + + callback = baseCreateCallback(callback, thisArg, 3); + while (length--) { + var key = props[length]; + if (callback(object[key], key, object) === false) { + break; + } + } + return object; + } + + /** + * Creates a sorted array of property names of all enumerable properties, + * own and inherited, of `object` that have function values. + * + * @static + * @memberOf _ + * @alias methods + * @category Objects + * @param {Object} object The object to inspect. + * @returns {Array} Returns an array of property names that have function values. + * @example + * + * _.functions(_); + * // => ['all', 'any', 'bind', 'bindAll', 'clone', 'compact', 'compose', ...] + */ + function functions(object) { + var result = []; + forIn(object, function(value, key) { + if (isFunction(value)) { + result.push(key); + } + }); + return result.sort(); + } + + /** + * Checks if the specified object `property` exists and is a direct property, + * instead of an inherited property. + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The object to check. + * @param {string} property The property to check for. + * @returns {boolean} Returns `true` if key is a direct property, else `false`. + * @example + * + * _.has({ 'a': 1, 'b': 2, 'c': 3 }, 'b'); + * // => true + */ + function has(object, property) { + return object ? hasOwnProperty.call(object, property) : false; + } + + /** + * Creates an object composed of the inverted keys and values of the given object. + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The object to invert. + * @returns {Object} Returns the created inverted object. + * @example + * + * _.invert({ 'first': 'moe', 'second': 'larry' }); + * // => { 'moe': 'first', 'larry': 'second' } + */ + function invert(object) { + var index = -1, + props = keys(object), + length = props.length, + result = {}; + + while (++index < length) { + var key = props[index]; + result[object[key]] = key; + } + return result; + } + + /** + * Checks if `value` is a boolean value. + * + * @static + * @memberOf _ + * @category Objects + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if the `value` is a boolean value, else `false`. + * @example + * + * _.isBoolean(null); + * // => false + */ + function isBoolean(value) { + return value === true || value === false || toString.call(value) == boolClass; + } + + /** + * Checks if `value` is a date. + * + * @static + * @memberOf _ + * @category Objects + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if the `value` is a date, else `false`. + * @example + * + * _.isDate(new Date); + * // => true + */ + function isDate(value) { + return value ? (typeof value == 'object' && toString.call(value) == dateClass) : false; + } + + /** + * Checks if `value` is a DOM element. + * + * @static + * @memberOf _ + * @category Objects + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if the `value` is a DOM element, else `false`. + * @example + * + * _.isElement(document.body); + * // => true + */ + function isElement(value) { + return value ? value.nodeType === 1 : false; + } + + /** + * Checks if `value` is empty. Arrays, strings, or `arguments` objects with a + * length of `0` and objects with no own enumerable properties are considered + * "empty". + * + * @static + * @memberOf _ + * @category Objects + * @param {Array|Object|string} value The value to inspect. + * @returns {boolean} Returns `true` if the `value` is empty, else `false`. + * @example + * + * _.isEmpty([1, 2, 3]); + * // => false + * + * _.isEmpty({}); + * // => true + * + * _.isEmpty(''); + * // => true + */ + function isEmpty(value) { + var result = true; + if (!value) { + return result; + } + var className = toString.call(value), + length = value.length; + + if ((className == arrayClass || className == stringClass || + (support.argsClass ? className == argsClass : isArguments(value))) || + (className == objectClass && typeof length == 'number' && isFunction(value.splice))) { + return !length; + } + forOwn(value, function() { + return (result = false); + }); + return result; + } + + /** + * Performs a deep comparison between two values to determine if they are + * equivalent to each other. If a callback is provided it will be executed + * to compare values. If the callback returns `undefined` comparisons will + * be handled by the method instead. The callback is bound to `thisArg` and + * invoked with two arguments; (a, b). + * + * @static + * @memberOf _ + * @category Objects + * @param {*} a The value to compare. + * @param {*} b The other value to compare. + * @param {Function} [callback] The function to customize comparing values. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {boolean} Returns `true` if the values are equivalent, else `false`. + * @example + * + * var moe = { 'name': 'moe', 'age': 40 }; + * var copy = { 'name': 'moe', 'age': 40 }; + * + * moe == copy; + * // => false + * + * _.isEqual(moe, copy); + * // => true + * + * var words = ['hello', 'goodbye']; + * var otherWords = ['hi', 'goodbye']; + * + * _.isEqual(words, otherWords, function(a, b) { + * var reGreet = /^(?:hello|hi)$/i, + * aGreet = _.isString(a) && reGreet.test(a), + * bGreet = _.isString(b) && reGreet.test(b); + * + * return (aGreet || bGreet) ? (aGreet == bGreet) : undefined; + * }); + * // => true + */ + function isEqual(a, b, callback, thisArg) { + return baseIsEqual(a, b, typeof callback == 'function' && baseCreateCallback(callback, thisArg, 2)); + } + + /** + * Checks if `value` is, or can be coerced to, a finite number. + * + * Note: This is not the same as native `isFinite` which will return true for + * booleans and empty strings. See http://es5.github.io/#x15.1.2.5. + * + * @static + * @memberOf _ + * @category Objects + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if the `value` is finite, else `false`. + * @example + * + * _.isFinite(-101); + * // => true + * + * _.isFinite('10'); + * // => true + * + * _.isFinite(true); + * // => false + * + * _.isFinite(''); + * // => false + * + * _.isFinite(Infinity); + * // => false + */ + function isFinite(value) { + return nativeIsFinite(value) && !nativeIsNaN(parseFloat(value)); + } + + /** + * Checks if `value` is a function. + * + * @static + * @memberOf _ + * @category Objects + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if the `value` is a function, else `false`. + * @example + * + * _.isFunction(_); + * // => true + */ + function isFunction(value) { + return typeof value == 'function'; + } + // fallback for older versions of Chrome and Safari + if (isFunction(/x/)) { + isFunction = function(value) { + return typeof value == 'function' && toString.call(value) == funcClass; + }; + } + + /** + * Checks if `value` is the language type of Object. + * (e.g. arrays, functions, objects, regexes, `new Number(0)`, and `new String('')`) + * + * @static + * @memberOf _ + * @category Objects + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if the `value` is an object, else `false`. + * @example + * + * _.isObject({}); + * // => true + * + * _.isObject([1, 2, 3]); + * // => true + * + * _.isObject(1); + * // => false + */ + function isObject(value) { + // check if the value is the ECMAScript language type of Object + // http://es5.github.io/#x8 + // and avoid a V8 bug + // http://code.google.com/p/v8/issues/detail?id=2291 + return !!(value && objectTypes[typeof value]); + } + + /** + * Checks if `value` is `NaN`. + * + * Note: This is not the same as native `isNaN` which will return `true` for + * `undefined` and other non-numeric values. See http://es5.github.io/#x15.1.2.4. + * + * @static + * @memberOf _ + * @category Objects + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if the `value` is `NaN`, else `false`. + * @example + * + * _.isNaN(NaN); + * // => true + * + * _.isNaN(new Number(NaN)); + * // => true + * + * isNaN(undefined); + * // => true + * + * _.isNaN(undefined); + * // => false + */ + function isNaN(value) { + // `NaN` as a primitive is the only value that is not equal to itself + // (perform the [[Class]] check first to avoid errors with some host objects in IE) + return isNumber(value) && value != +value; + } + + /** + * Checks if `value` is `null`. + * + * @static + * @memberOf _ + * @category Objects + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if the `value` is `null`, else `false`. + * @example + * + * _.isNull(null); + * // => true + * + * _.isNull(undefined); + * // => false + */ + function isNull(value) { + return value === null; + } + + /** + * Checks if `value` is a number. + * + * Note: `NaN` is considered a number. See http://es5.github.io/#x8.5. + * + * @static + * @memberOf _ + * @category Objects + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if the `value` is a number, else `false`. + * @example + * + * _.isNumber(8.4 * 5); + * // => true + */ + function isNumber(value) { + return typeof value == 'number' || toString.call(value) == numberClass; + } + + /** + * Checks if `value` is an object created by the `Object` constructor. + * + * @static + * @memberOf _ + * @category Objects + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a plain object, else `false`. + * @example + * + * function Stooge(name, age) { + * this.name = name; + * this.age = age; + * } + * + * _.isPlainObject(new Stooge('moe', 40)); + * // => false + * + * _.isPlainObject([1, 2, 3]); + * // => false + * + * _.isPlainObject({ 'name': 'moe', 'age': 40 }); + * // => true + */ + var isPlainObject = !getPrototypeOf ? shimIsPlainObject : function(value) { + if (!(value && toString.call(value) == objectClass) || (!support.argsClass && isArguments(value))) { + return false; + } + var valueOf = value.valueOf, + objProto = typeof valueOf == 'function' && (objProto = getPrototypeOf(valueOf)) && getPrototypeOf(objProto); + + return objProto + ? (value == objProto || getPrototypeOf(value) == objProto) + : shimIsPlainObject(value); + }; + + /** + * Checks if `value` is a regular expression. + * + * @static + * @memberOf _ + * @category Objects + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if the `value` is a regular expression, else `false`. + * @example + * + * _.isRegExp(/moe/); + * // => true + */ + function isRegExp(value) { + return (value && objectTypes[typeof value]) ? toString.call(value) == regexpClass : false; + } + + /** + * Checks if `value` is a string. + * + * @static + * @memberOf _ + * @category Objects + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if the `value` is a string, else `false`. + * @example + * + * _.isString('moe'); + * // => true + */ + function isString(value) { + return typeof value == 'string' || toString.call(value) == stringClass; + } + + /** + * Checks if `value` is `undefined`. + * + * @static + * @memberOf _ + * @category Objects + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if the `value` is `undefined`, else `false`. + * @example + * + * _.isUndefined(void 0); + * // => true + */ + function isUndefined(value) { + return typeof value == 'undefined'; + } + + /** + * Recursively merges own enumerable properties of the source object(s), that + * don't resolve to `undefined` into the destination object. Subsequent sources + * will overwrite property assignments of previous sources. If a callback is + * provided it will be executed to produce the merged values of the destination + * and source properties. If the callback returns `undefined` merging will + * be handled by the method instead. The callback is bound to `thisArg` and + * invoked with two arguments; (objectValue, sourceValue). + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The destination object. + * @param {...Object} [source] The source objects. + * @param {Function} [callback] The function to customize merging properties. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {Object} Returns the destination object. + * @example + * + * var names = { + * 'stooges': [ + * { 'name': 'moe' }, + * { 'name': 'larry' } + * ] + * }; + * + * var ages = { + * 'stooges': [ + * { 'age': 40 }, + * { 'age': 50 } + * ] + * }; + * + * _.merge(names, ages); + * // => { 'stooges': [{ 'name': 'moe', 'age': 40 }, { 'name': 'larry', 'age': 50 }] } + * + * var food = { + * 'fruits': ['apple'], + * 'vegetables': ['beet'] + * }; + * + * var otherFood = { + * 'fruits': ['banana'], + * 'vegetables': ['carrot'] + * }; + * + * _.merge(food, otherFood, function(a, b) { + * return _.isArray(a) ? a.concat(b) : undefined; + * }); + * // => { 'fruits': ['apple', 'banana'], 'vegetables': ['beet', 'carrot] } + */ + function merge(object) { + var args = arguments, + length = 2; + + if (!isObject(object)) { + return object; + } + // allows working with `_.reduce` and `_.reduceRight` without using + // their `index` and `collection` arguments + if (typeof args[2] != 'number') { + length = args.length; + } + if (length > 3 && typeof args[length - 2] == 'function') { + var callback = baseCreateCallback(args[--length - 1], args[length--], 2); + } else if (length > 2 && typeof args[length - 1] == 'function') { + callback = args[--length]; + } + var sources = nativeSlice.call(arguments, 1, length), + index = -1, + stackA = getArray(), + stackB = getArray(); + + while (++index < length) { + baseMerge(object, sources[index], callback, stackA, stackB); + } + releaseArray(stackA); + releaseArray(stackB); + return object; + } + + /** + * Creates a shallow clone of `object` excluding the specified properties. + * Property names may be specified as individual arguments or as arrays of + * property names. If a callback is provided it will be executed for each + * property of `object` omitting the properties the callback returns truey + * for. The callback is bound to `thisArg` and invoked with three arguments; + * (value, key, object). + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The source object. + * @param {Function|...string|string[]} [callback] The properties to omit or the + * function called per iteration. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {Object} Returns an object without the omitted properties. + * @example + * + * _.omit({ 'name': 'moe', 'age': 40 }, 'age'); + * // => { 'name': 'moe' } + * + * _.omit({ 'name': 'moe', 'age': 40 }, function(value) { + * return typeof value == 'number'; + * }); + * // => { 'name': 'moe' } + */ + function omit(object, callback, thisArg) { + var indexOf = getIndexOf(), + isFunc = typeof callback == 'function', + result = {}; + + if (isFunc) { + callback = lodash.createCallback(callback, thisArg, 3); + } else { + var props = baseFlatten(arguments, true, false, 1); + } + forIn(object, function(value, key, object) { + if (isFunc + ? !callback(value, key, object) + : indexOf(props, key) < 0 + ) { + result[key] = value; + } + }); + return result; + } + + /** + * Creates a two dimensional array of an object's key-value pairs, + * i.e. `[[key1, value1], [key2, value2]]`. + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The object to inspect. + * @returns {Array} Returns new array of key-value pairs. + * @example + * + * _.pairs({ 'moe': 30, 'larry': 40 }); + * // => [['moe', 30], ['larry', 40]] (property order is not guaranteed across environments) + */ + function pairs(object) { + var index = -1, + props = keys(object), + length = props.length, + result = Array(length); + + while (++index < length) { + var key = props[index]; + result[index] = [key, object[key]]; + } + return result; + } + + /** + * Creates a shallow clone of `object` composed of the specified properties. + * Property names may be specified as individual arguments or as arrays of + * property names. If a callback is provided it will be executed for each + * property of `object` picking the properties the callback returns truey + * for. The callback is bound to `thisArg` and invoked with three arguments; + * (value, key, object). + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The source object. + * @param {Function|...string|string[]} [callback] The function called per + * iteration or property names to pick, specified as individual property + * names or arrays of property names. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {Object} Returns an object composed of the picked properties. + * @example + * + * _.pick({ 'name': 'moe', '_userid': 'moe1' }, 'name'); + * // => { 'name': 'moe' } + * + * _.pick({ 'name': 'moe', '_userid': 'moe1' }, function(value, key) { + * return key.charAt(0) != '_'; + * }); + * // => { 'name': 'moe' } + */ + function pick(object, callback, thisArg) { + var result = {}; + if (typeof callback != 'function') { + var index = -1, + props = baseFlatten(arguments, true, false, 1), + length = isObject(object) ? props.length : 0; + + while (++index < length) { + var key = props[index]; + if (key in object) { + result[key] = object[key]; + } + } + } else { + callback = lodash.createCallback(callback, thisArg, 3); + forIn(object, function(value, key, object) { + if (callback(value, key, object)) { + result[key] = value; + } + }); + } + return result; + } - /** - * Iterates over a `collection`, executing the `callback` for each element in - * the `collection`. The `callback` is bound to `thisArg` and invoked with 3 - * arguments; (value, index|key, collection). Callbacks may exit iteration - * early by explicitly returning `false`. - * - * @static - * @memberOf _ - * @alias each - * @category Collections - * @param {Array|Object|String} collection The collection to iterate over. - * @param {Function} callback The function called per iteration. - * @param {Mixed} [thisArg] The `this` binding for the callback. - * @returns {Array|Object} Returns `collection`. - * @example - * - * _([1, 2, 3]).forEach(alert).join(','); - * // => alerts each number and returns '1,2,3' - * - * _.forEach({ 'one': 1, 'two': 2, 'three': 3 }, alert); - * // => alerts each number (order is not guaranteed) - */ - var forEach = createIterator(baseIteratorOptions, forEachIteratorOptions); + /** + * An alternative to `_.reduce` this method transforms `object` to a new + * `accumulator` object which is the result of running each of its elements + * through a callback, with each callback execution potentially mutating + * the `accumulator` object. The callback is bound to `thisArg` and invoked + * with four arguments; (accumulator, value, key, object). Callbacks may exit + * iteration early by explicitly returning `false`. + * + * @static + * @memberOf _ + * @category Objects + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [callback=identity] The function called per iteration. + * @param {*} [accumulator] The custom accumulator value. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {*} Returns the accumulated value. + * @example + * + * var squares = _.transform([1, 2, 3, 4, 5, 6, 7, 8, 9, 10], function(result, num) { + * num *= num; + * if (num % 2) { + * return result.push(num) < 3; + * } + * }); + * // => [1, 9, 25] + * + * var mapped = _.transform({ 'a': 1, 'b': 2, 'c': 3 }, function(result, num, key) { + * result[key] = num * 3; + * }); + * // => { 'a': 3, 'b': 6, 'c': 9 } + */ + function transform(object, callback, accumulator, thisArg) { + var isArr = isArray(object); + callback = baseCreateCallback(callback, thisArg, 4); + + if (accumulator == null) { + if (isArr) { + accumulator = []; + } else { + var ctor = object && object.constructor, + proto = ctor && ctor.prototype; + + accumulator = createObject(proto); + } + } + (isArr ? baseEach : forOwn)(object, function(value, index, object) { + return callback(accumulator, value, index, object); + }); + return accumulator; + } + + /** + * Creates an array composed of the own enumerable property values of `object`. + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The object to inspect. + * @returns {Array} Returns an array of property values. + * @example + * + * _.values({ 'one': 1, 'two': 2, 'three': 3 }); + * // => [1, 2, 3] (property order is not guaranteed across environments) + */ + function values(object) { + var index = -1, + props = keys(object), + length = props.length, + result = Array(length); + + while (++index < length) { + result[index] = object[props[index]]; + } + return result; + } + + /*--------------------------------------------------------------------------*/ + + /** + * Creates an array of elements from the specified indexes, or keys, of the + * `collection`. Indexes may be specified as individual arguments or as arrays + * of indexes. + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|string} collection The collection to iterate over. + * @param {...(number|number[]|string|string[])} [index] The indexes of `collection` + * to retrieve, specified as individual indexes or arrays of indexes. + * @returns {Array} Returns a new array of elements corresponding to the + * provided indexes. + * @example + * + * _.at(['a', 'b', 'c', 'd', 'e'], [0, 2, 4]); + * // => ['a', 'c', 'e'] + * + * _.at(['moe', 'larry', 'curly'], 0, 2); + * // => ['moe', 'curly'] + */ + function at(collection) { + var args = arguments, + index = -1, + props = baseFlatten(args, true, false, 1), + length = (args[2] && args[2][args[1]] === collection) ? 1 : props.length, + result = Array(length); + + if (support.unindexedChars && isString(collection)) { + collection = collection.split(''); + } + while(++index < length) { + result[index] = collection[props[index]]; + } + return result; + } + + /** + * Checks if a given value is present in a collection using strict equality + * for comparisons, i.e. `===`. If `fromIndex` is negative, it is used as the + * offset from the end of the collection. + * + * @static + * @memberOf _ + * @alias include + * @category Collections + * @param {Array|Object|string} collection The collection to iterate over. + * @param {*} target The value to check for. + * @param {number} [fromIndex=0] The index to search from. + * @returns {boolean} Returns `true` if the `target` element is found, else `false`. + * @example + * + * _.contains([1, 2, 3], 1); + * // => true + * + * _.contains([1, 2, 3], 1, 2); + * // => false + * + * _.contains({ 'name': 'moe', 'age': 40 }, 'moe'); + * // => true + * + * _.contains('curly', 'ur'); + * // => true + */ + function contains(collection, target, fromIndex) { + var index = -1, + indexOf = getIndexOf(), + length = collection ? collection.length : 0, + result = false; + + fromIndex = (fromIndex < 0 ? nativeMax(0, length + fromIndex) : fromIndex) || 0; + if (isArray(collection)) { + result = indexOf(collection, target, fromIndex) > -1; + } else if (typeof length == 'number') { + result = (isString(collection) ? collection.indexOf(target, fromIndex) : indexOf(collection, target, fromIndex)) > -1; + } else { + baseEach(collection, function(value) { + if (++index >= fromIndex) { + return !(result = value === target); + } + }); + } + return result; + } + + /** + * Creates an object composed of keys generated from the results of running + * each element of `collection` through the callback. The corresponding value + * of each key is the number of times the key was returned by the callback. + * The callback is bound to `thisArg` and invoked with three arguments; + * (value, index|key, collection). + * + * If a property name is provided for `callback` the created "_.pluck" style + * callback will return the property value of the given element. + * + * If an object is provided for `callback` the created "_.where" style callback + * will return `true` for elements that have the properties of the given object, + * else `false`. + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|string} collection The collection to iterate over. + * @param {Function|Object|string} [callback=identity] The function called + * per iteration. If a property name or object is provided it will be used + * to create a "_.pluck" or "_.where" style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {Object} Returns the composed aggregate object. + * @example + * + * _.countBy([4.3, 6.1, 6.4], function(num) { return Math.floor(num); }); + * // => { '4': 1, '6': 2 } + * + * _.countBy([4.3, 6.1, 6.4], function(num) { return this.floor(num); }, Math); + * // => { '4': 1, '6': 2 } + * + * _.countBy(['one', 'two', 'three'], 'length'); + * // => { '3': 2, '5': 1 } + */ + var countBy = createAggregator(function(result, value, key) { + (hasOwnProperty.call(result, key) ? result[key]++ : result[key] = 1); + }); + + /** + * Checks if the given callback returns truey value for **all** elements of + * a collection. The callback is bound to `thisArg` and invoked with three + * arguments; (value, index|key, collection). + * + * If a property name is provided for `callback` the created "_.pluck" style + * callback will return the property value of the given element. + * + * If an object is provided for `callback` the created "_.where" style callback + * will return `true` for elements that have the properties of the given object, + * else `false`. + * + * @static + * @memberOf _ + * @alias all + * @category Collections + * @param {Array|Object|string} collection The collection to iterate over. + * @param {Function|Object|string} [callback=identity] The function called + * per iteration. If a property name or object is provided it will be used + * to create a "_.pluck" or "_.where" style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {boolean} Returns `true` if all elements passed the callback check, + * else `false`. + * @example + * + * _.every([true, 1, null, 'yes'], Boolean); + * // => false + * + * var stooges = [ + * { 'name': 'moe', 'age': 40 }, + * { 'name': 'larry', 'age': 50 } + * ]; + * + * // using "_.pluck" callback shorthand + * _.every(stooges, 'age'); + * // => true + * + * // using "_.where" callback shorthand + * _.every(stooges, { 'age': 50 }); + * // => false + */ + function every(collection, callback, thisArg) { + var result = true; + callback = lodash.createCallback(callback, thisArg, 3); + + if (isArray(collection)) { + var index = -1, + length = collection.length; + + while (++index < length) { + if (!(result = !!callback(collection[index], index, collection))) { + break; + } + } + } else { + baseEach(collection, function(value, index, collection) { + return (result = !!callback(value, index, collection)); + }); + } + return result; + } + + /** + * Iterates over elements of a collection, returning an array of all elements + * the callback returns truey for. The callback is bound to `thisArg` and + * invoked with three arguments; (value, index|key, collection). + * + * If a property name is provided for `callback` the created "_.pluck" style + * callback will return the property value of the given element. + * + * If an object is provided for `callback` the created "_.where" style callback + * will return `true` for elements that have the properties of the given object, + * else `false`. + * + * @static + * @memberOf _ + * @alias select + * @category Collections + * @param {Array|Object|string} collection The collection to iterate over. + * @param {Function|Object|string} [callback=identity] The function called + * per iteration. If a property name or object is provided it will be used + * to create a "_.pluck" or "_.where" style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {Array} Returns a new array of elements that passed the callback check. + * @example + * + * var evens = _.filter([1, 2, 3, 4, 5, 6], function(num) { return num % 2 == 0; }); + * // => [2, 4, 6] + * + * var food = [ + * { 'name': 'apple', 'organic': false, 'type': 'fruit' }, + * { 'name': 'carrot', 'organic': true, 'type': 'vegetable' } + * ]; + * + * // using "_.pluck" callback shorthand + * _.filter(food, 'organic'); + * // => [{ 'name': 'carrot', 'organic': true, 'type': 'vegetable' }] + * + * // using "_.where" callback shorthand + * _.filter(food, { 'type': 'fruit' }); + * // => [{ 'name': 'apple', 'organic': false, 'type': 'fruit' }] + */ + function filter(collection, callback, thisArg) { + var result = []; + callback = lodash.createCallback(callback, thisArg, 3); + + if (isArray(collection)) { + var index = -1, + length = collection.length; + + while (++index < length) { + var value = collection[index]; + if (callback(value, index, collection)) { + result.push(value); + } + } + } else { + baseEach(collection, function(value, index, collection) { + if (callback(value, index, collection)) { + result.push(value); + } + }); + } + return result; + } + + /** + * Iterates over elements of a collection, returning the first element that + * the callback returns truey for. The callback is bound to `thisArg` and + * invoked with three arguments; (value, index|key, collection). + * + * If a property name is provided for `callback` the created "_.pluck" style + * callback will return the property value of the given element. + * + * If an object is provided for `callback` the created "_.where" style callback + * will return `true` for elements that have the properties of the given object, + * else `false`. + * + * @static + * @memberOf _ + * @alias detect, findWhere + * @category Collections + * @param {Array|Object|string} collection The collection to iterate over. + * @param {Function|Object|string} [callback=identity] The function called + * per iteration. If a property name or object is provided it will be used + * to create a "_.pluck" or "_.where" style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {*} Returns the found element, else `undefined`. + * @example + * + * _.find([1, 2, 3, 4], function(num) { + * return num % 2 == 0; + * }); + * // => 2 + * + * var food = [ + * { 'name': 'apple', 'organic': false, 'type': 'fruit' }, + * { 'name': 'banana', 'organic': true, 'type': 'fruit' }, + * { 'name': 'beet', 'organic': false, 'type': 'vegetable' } + * ]; + * + * // using "_.where" callback shorthand + * _.find(food, { 'type': 'vegetable' }); + * // => { 'name': 'beet', 'organic': false, 'type': 'vegetable' } + * + * // using "_.pluck" callback shorthand + * _.find(food, 'organic'); + * // => { 'name': 'banana', 'organic': true, 'type': 'fruit' } + */ + function find(collection, callback, thisArg) { + callback = lodash.createCallback(callback, thisArg, 3); + + if (isArray(collection)) { + var index = -1, + length = collection.length; + + while (++index < length) { + var value = collection[index]; + if (callback(value, index, collection)) { + return value; + } + } + } else { + var result; + baseEach(collection, function(value, index, collection) { + if (callback(value, index, collection)) { + result = value; + return false; + } + }); + return result; + } + } + + /** + * This method is like `_.find` except that it iterates over elements + * of a `collection` from right to left. + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|string} collection The collection to iterate over. + * @param {Function|Object|string} [callback=identity] The function called + * per iteration. If a property name or object is provided it will be used + * to create a "_.pluck" or "_.where" style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {*} Returns the found element, else `undefined`. + * @example + * + * _.findLast([1, 2, 3, 4], function(num) { + * return num % 2 == 1; + * }); + * // => 3 + */ + function findLast(collection, callback, thisArg) { + var result; + callback = lodash.createCallback(callback, thisArg, 3); + forEachRight(collection, function(value, index, collection) { + if (callback(value, index, collection)) { + result = value; + return false; + } + }); + return result; + } + + /** + * Iterates over elements of a collection, executing the callback for each + * element. The callback is bound to `thisArg` and invoked with three arguments; + * (value, index|key, collection). Callbacks may exit iteration early by + * explicitly returning `false`. + * + * @static + * @memberOf _ + * @alias each + * @category Collections + * @param {Array|Object|string} collection The collection to iterate over. + * @param {Function} [callback=identity] The function called per iteration. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {Array|Object|string} Returns `collection`. + * @example + * + * _([1, 2, 3]).forEach(function(num) { console.log(num); }).join(','); + * // => logs each number and returns '1,2,3' + * + * _.forEach({ 'one': 1, 'two': 2, 'three': 3 }, function(num) { console.log(num); }); + * // => logs each number and returns the object (property order is not guaranteed across environments) + */ + function forEach(collection, callback, thisArg) { + if (callback && typeof thisArg == 'undefined' && isArray(collection)) { + var index = -1, + length = collection.length; + + while (++index < length) { + if (callback(collection[index], index, collection) === false) { + break; + } + } + } else { + baseEach(collection, callback, thisArg); + } + return collection; + } + + /** + * This method is like `_.forEach` except that it iterates over elements + * of a `collection` from right to left. + * + * @static + * @memberOf _ + * @alias eachRight + * @category Collections + * @param {Array|Object|string} collection The collection to iterate over. + * @param {Function} [callback=identity] The function called per iteration. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {Array|Object|string} Returns `collection`. + * @example + * + * _([1, 2, 3]).forEachRight(function(num) { console.log(num); }).join(','); + * // => logs each number from right to left and returns '3,2,1' + */ + function forEachRight(collection, callback, thisArg) { + var iterable = collection, + length = collection ? collection.length : 0; + + callback = callback && typeof thisArg == 'undefined' ? callback : baseCreateCallback(callback, thisArg, 3); + if (isArray(collection)) { + while (length--) { + if (callback(collection[length], length, collection) === false) { + break; + } + } + } else { + if (typeof length != 'number') { + var props = keys(collection); + length = props.length; + } else if (support.unindexedChars && isString(collection)) { + iterable = collection.split(''); + } + baseEach(collection, function(value, key, collection) { + key = props ? props[--length] : --length; + return callback(iterable[key], key, collection); + }); + } + return collection; + } + + /** + * Creates an object composed of keys generated from the results of running + * each element of a collection through the callback. The corresponding value + * of each key is an array of the elements responsible for generating the key. + * The callback is bound to `thisArg` and invoked with three arguments; + * (value, index|key, collection). + * + * If a property name is provided for `callback` the created "_.pluck" style + * callback will return the property value of the given element. + * + * If an object is provided for `callback` the created "_.where" style callback + * will return `true` for elements that have the properties of the given object, + * else `false` + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|string} collection The collection to iterate over. + * @param {Function|Object|string} [callback=identity] The function called + * per iteration. If a property name or object is provided it will be used + * to create a "_.pluck" or "_.where" style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {Object} Returns the composed aggregate object. + * @example + * + * _.groupBy([4.2, 6.1, 6.4], function(num) { return Math.floor(num); }); + * // => { '4': [4.2], '6': [6.1, 6.4] } + * + * _.groupBy([4.2, 6.1, 6.4], function(num) { return this.floor(num); }, Math); + * // => { '4': [4.2], '6': [6.1, 6.4] } + * + * // using "_.pluck" callback shorthand + * _.groupBy(['one', 'two', 'three'], 'length'); + * // => { '3': ['one', 'two'], '5': ['three'] } + */ + var groupBy = createAggregator(function(result, value, key) { + (hasOwnProperty.call(result, key) ? result[key] : result[key] = []).push(value); + }); + + /** + * Creates an object composed of keys generated from the results of running + * each element of the collection through the given callback. The corresponding + * value of each key is the last element responsible for generating the key. + * The callback is bound to `thisArg` and invoked with three arguments; + * (value, index|key, collection). + * + * If a property name is provided for `callback` the created "_.pluck" style + * callback will return the property value of the given element. + * + * If an object is provided for `callback` the created "_.where" style callback + * will return `true` for elements that have the properties of the given object, + * else `false`. + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|string} collection The collection to iterate over. + * @param {Function|Object|string} [callback=identity] The function called + * per iteration. If a property name or object is provided it will be used + * to create a "_.pluck" or "_.where" style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {Object} Returns the composed aggregate object. + * @example + * + * var keys = [ + * { 'dir': 'left', 'code': 97 }, + * { 'dir': 'right', 'code': 100 } + * ]; + * + * _.indexBy(keys, 'dir'); + * // => { 'left': { 'dir': 'left', 'code': 97 }, 'right': { 'dir': 'right', 'code': 100 } } + * + * _.indexBy(keys, function(key) { return String.fromCharCode(key.code); }); + * // => { 'a': { 'dir': 'left', 'code': 97 }, 'd': { 'dir': 'right', 'code': 100 } } + * + * _.indexBy(stooges, function(key) { this.fromCharCode(key.code); }, String); + * // => { 'a': { 'dir': 'left', 'code': 97 }, 'd': { 'dir': 'right', 'code': 100 } } + */ + var indexBy = createAggregator(function(result, value, key) { + result[key] = value; + }); + + /** + * Invokes the method named by `methodName` on each element in the `collection` + * returning an array of the results of each invoked method. Additional arguments + * will be provided to each invoked method. If `methodName` is a function it + * will be invoked for, and `this` bound to, each element in the `collection`. + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|string} collection The collection to iterate over. + * @param {Function|string} methodName The name of the method to invoke or + * the function invoked per iteration. + * @param {...*} [arg] Arguments to invoke the method with. + * @returns {Array} Returns a new array of the results of each invoked method. + * @example + * + * _.invoke([[5, 1, 7], [3, 2, 1]], 'sort'); + * // => [[1, 5, 7], [1, 2, 3]] + * + * _.invoke([123, 456], String.prototype.split, ''); + * // => [['1', '2', '3'], ['4', '5', '6']] + */ + function invoke(collection, methodName) { + var args = nativeSlice.call(arguments, 2), + index = -1, + isFunc = typeof methodName == 'function', + length = collection ? collection.length : 0, + result = Array(typeof length == 'number' ? length : 0); + + forEach(collection, function(value) { + result[++index] = (isFunc ? methodName : value[methodName]).apply(value, args); + }); + return result; + } + + /** + * Creates an array of values by running each element in the collection + * through the callback. The callback is bound to `thisArg` and invoked with + * three arguments; (value, index|key, collection). + * + * If a property name is provided for `callback` the created "_.pluck" style + * callback will return the property value of the given element. + * + * If an object is provided for `callback` the created "_.where" style callback + * will return `true` for elements that have the properties of the given object, + * else `false`. + * + * @static + * @memberOf _ + * @alias collect + * @category Collections + * @param {Array|Object|string} collection The collection to iterate over. + * @param {Function|Object|string} [callback=identity] The function called + * per iteration. If a property name or object is provided it will be used + * to create a "_.pluck" or "_.where" style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {Array} Returns a new array of the results of each `callback` execution. + * @example + * + * _.map([1, 2, 3], function(num) { return num * 3; }); + * // => [3, 6, 9] + * + * _.map({ 'one': 1, 'two': 2, 'three': 3 }, function(num) { return num * 3; }); + * // => [3, 6, 9] (property order is not guaranteed across environments) + * + * var stooges = [ + * { 'name': 'moe', 'age': 40 }, + * { 'name': 'larry', 'age': 50 } + * ]; + * + * // using "_.pluck" callback shorthand + * _.map(stooges, 'name'); + * // => ['moe', 'larry'] + */ + function map(collection, callback, thisArg) { + var index = -1, + length = collection ? collection.length : 0, + result = Array(typeof length == 'number' ? length : 0); + + callback = lodash.createCallback(callback, thisArg, 3); + if (isArray(collection)) { + while (++index < length) { + result[index] = callback(collection[index], index, collection); + } + } else { + baseEach(collection, function(value, key, collection) { + result[++index] = callback(value, key, collection); + }); + } + return result; + } + + /** + * Retrieves the maximum value of a collection. If the collection is empty or + * falsey `-Infinity` is returned. If a callback is provided it will be executed + * for each value in the collection to generate the criterion by which the value + * is ranked. The callback is bound to `thisArg` and invoked with three + * arguments; (value, index, collection). + * + * If a property name is provided for `callback` the created "_.pluck" style + * callback will return the property value of the given element. + * + * If an object is provided for `callback` the created "_.where" style callback + * will return `true` for elements that have the properties of the given object, + * else `false`. + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|string} collection The collection to iterate over. + * @param {Function|Object|string} [callback=identity] The function called + * per iteration. If a property name or object is provided it will be used + * to create a "_.pluck" or "_.where" style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {*} Returns the maximum value. + * @example + * + * _.max([4, 2, 8, 6]); + * // => 8 + * + * var stooges = [ + * { 'name': 'moe', 'age': 40 }, + * { 'name': 'larry', 'age': 50 } + * ]; + * + * _.max(stooges, function(stooge) { return stooge.age; }); + * // => { 'name': 'larry', 'age': 50 }; + * + * // using "_.pluck" callback shorthand + * _.max(stooges, 'age'); + * // => { 'name': 'larry', 'age': 50 }; + */ + function max(collection, callback, thisArg) { + var computed = -Infinity, + result = computed; + + if (!callback && isArray(collection)) { + var index = -1, + length = collection.length; + + while (++index < length) { + var value = collection[index]; + if (value > result) { + result = value; + } + } + } else { + callback = (!callback && isString(collection)) + ? charAtCallback + : lodash.createCallback(callback, thisArg, 3); + + baseEach(collection, function(value, index, collection) { + var current = callback(value, index, collection); + if (current > computed) { + computed = current; + result = value; + } + }); + } + return result; + } + + /** + * Retrieves the minimum value of a collection. If the collection is empty or + * falsey `Infinity` is returned. If a callback is provided it will be executed + * for each value in the collection to generate the criterion by which the value + * is ranked. The callback is bound to `thisArg` and invoked with three + * arguments; (value, index, collection). + * + * If a property name is provided for `callback` the created "_.pluck" style + * callback will return the property value of the given element. + * + * If an object is provided for `callback` the created "_.where" style callback + * will return `true` for elements that have the properties of the given object, + * else `false`. + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|string} collection The collection to iterate over. + * @param {Function|Object|string} [callback=identity] The function called + * per iteration. If a property name or object is provided it will be used + * to create a "_.pluck" or "_.where" style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {*} Returns the minimum value. + * @example + * + * _.min([4, 2, 8, 6]); + * // => 2 + * + * var stooges = [ + * { 'name': 'moe', 'age': 40 }, + * { 'name': 'larry', 'age': 50 } + * ]; + * + * _.min(stooges, function(stooge) { return stooge.age; }); + * // => { 'name': 'moe', 'age': 40 }; + * + * // using "_.pluck" callback shorthand + * _.min(stooges, 'age'); + * // => { 'name': 'moe', 'age': 40 }; + */ + function min(collection, callback, thisArg) { + var computed = Infinity, + result = computed; + + if (!callback && isArray(collection)) { + var index = -1, + length = collection.length; + + while (++index < length) { + var value = collection[index]; + if (value < result) { + result = value; + } + } + } else { + callback = (!callback && isString(collection)) + ? charAtCallback + : lodash.createCallback(callback, thisArg, 3); + + baseEach(collection, function(value, index, collection) { + var current = callback(value, index, collection); + if (current < computed) { + computed = current; + result = value; + } + }); + } + return result; + } - /** - * Creates an object composed of keys returned from running each element of - * `collection` through a `callback`. The corresponding value of each key is an - * array of elements passed to `callback` that returned the key. The `callback` - * is bound to `thisArg` and invoked with 3 arguments; (value, index|key, collection). - * The `callback` argument may also be the name of a property to count by (e.g. 'length'). - * - * @static - * @memberOf _ - * @category Collections - * @param {Array|Object|String} collection The collection to iterate over. - * @param {Function|String} callback|property The function called per iteration - * or property name to group by. - * @param {Mixed} [thisArg] The `this` binding for the callback. - * @returns {Object} Returns the composed aggregate object. - * @example - * - * _.groupBy([4.2, 6.1, 6.4], function(num) { return Math.floor(num); }); - * // => { '4': [4.2], '6': [6.1, 6.4] } - * - * _.groupBy([4.2, 6.1, 6.4], function(num) { return this.floor(num); }, Math); - * // => { '4': [4.2], '6': [6.1, 6.4] } - * - * _.groupBy(['one', 'two', 'three'], 'length'); - * // => { '3': ['one', 'two'], '5': ['three'] } - */ - var groupBy = createIterator(baseIteratorOptions, countByIteratorOptions, { - 'inLoop': - 'prop = callback(value, index, collection);\n' + - '(hasOwnProperty.call(result, prop) ? result[prop] : result[prop] = []).push(value)' - }); + /** + * Retrieves the value of a specified property from all elements in the `collection`. + * + * @static + * @memberOf _ + * @type Function + * @category Collections + * @param {Array|Object|string} collection The collection to iterate over. + * @param {string} property The property to pluck. + * @returns {Array} Returns a new array of property values. + * @example + * + * var stooges = [ + * { 'name': 'moe', 'age': 40 }, + * { 'name': 'larry', 'age': 50 } + * ]; + * + * _.pluck(stooges, 'name'); + * // => ['moe', 'larry'] + */ + var pluck = map; - /** - * Invokes the method named by `methodName` on each element in the `collection`. - * Additional arguments will be passed to each invoked method. If `methodName` - * is a function it will be invoked for, and `this` bound to, each element - * in the `collection`. - * - * @static - * @memberOf _ - * @category Collections - * @param {Array|Object|String} collection The collection to iterate over. - * @param {Function|String} methodName The name of the method to invoke or - * the function invoked per iteration. - * @param {Mixed} [arg1, arg2, ...] Arguments to invoke the method with. - * @returns {Array} Returns a new array of values returned from each invoked method. - * @example - * - * _.invoke([[5, 1, 7], [3, 2, 1]], 'sort'); - * // => [[1, 5, 7], [1, 2, 3]] - * - * _.invoke([123, 456], String.prototype.split, ''); - * // => [['1', '2', '3'], ['4', '5', '6']] - */ - var invoke = createIterator(mapIteratorOptions, { - 'args': 'collection, methodName', - 'top': - 'var args = slice.call(arguments, 2),\n' + - ' isFunc = typeof methodName == \'function\'', - 'inLoop': { - 'array': - 'result[index] = (isFunc ? methodName : value[methodName]).apply(value, args)', - 'object': - 'result' + (isKeysFast ? '[ownIndex] = ' : '.push') + - '((isFunc ? methodName : value[methodName]).apply(value, args))' - } - }); + /** + * Reduces a collection to a value which is the accumulated result of running + * each element in the collection through the callback, where each successive + * callback execution consumes the return value of the previous execution. If + * `accumulator` is not provided the first element of the collection will be + * used as the initial `accumulator` value. The callback is bound to `thisArg` + * and invoked with four arguments; (accumulator, value, index|key, collection). + * + * @static + * @memberOf _ + * @alias foldl, inject + * @category Collections + * @param {Array|Object|string} collection The collection to iterate over. + * @param {Function} [callback=identity] The function called per iteration. + * @param {*} [accumulator] Initial value of the accumulator. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {*} Returns the accumulated value. + * @example + * + * var sum = _.reduce([1, 2, 3], function(sum, num) { + * return sum + num; + * }); + * // => 6 + * + * var mapped = _.reduce({ 'a': 1, 'b': 2, 'c': 3 }, function(result, num, key) { + * result[key] = num * 3; + * return result; + * }, {}); + * // => { 'a': 3, 'b': 6, 'c': 9 } + */ + function reduce(collection, callback, accumulator, thisArg) { + var noaccum = arguments.length < 3; + callback = baseCreateCallback(callback, thisArg, 4); - /** - * Creates a new array of values by running each element in the `collection` - * through a `callback`. The `callback` is bound to `thisArg` and invoked with - * 3 arguments; (value, index|key, collection). - * - * @static - * @memberOf _ - * @alias collect - * @category Collections - * @param {Array|Object|String} collection The collection to iterate over. - * @param {Function} [callback=identity] The function called per iteration. - * @param {Mixed} [thisArg] The `this` binding for the callback. - * @returns {Array} Returns a new array of elements returned by the callback. - * @example - * - * _.map([1, 2, 3], function(num) { return num * 3; }); - * // => [3, 6, 9] - * - * _.map({ 'one': 1, 'two': 2, 'three': 3 }, function(num) { return num * 3; }); - * // => [3, 6, 9] (order is not guaranteed) - */ - var map = createIterator(baseIteratorOptions, mapIteratorOptions); + if (isArray(collection)) { + var index = -1, + length = collection.length; - /** - * Retrieves the value of a specified property from all elements in - * the `collection`. - * - * @static - * @memberOf _ - * @category Collections - * @param {Array|Object|String} collection The collection to iterate over. - * @param {String} property The property to pluck. - * @returns {Array} Returns a new array of property values. - * @example - * - * var stooges = [ - * { 'name': 'moe', 'age': 40 }, - * { 'name': 'larry', 'age': 50 }, - * { 'name': 'curly', 'age': 60 } - * ]; - * - * _.pluck(stooges, 'name'); - * // => ['moe', 'larry', 'curly'] - */ - var pluck = createIterator(mapIteratorOptions, { - 'args': 'collection, property', - 'inLoop': { - 'array': 'result[index] = value[property]', - 'object': 'result' + (isKeysFast ? '[ownIndex] = ' : '.push') + '(value[property])' + if (noaccum) { + accumulator = collection[++index]; + } + while (++index < length) { + accumulator = callback(accumulator, collection[index], index, collection); + } + } else { + baseEach(collection, function(value, index, collection) { + accumulator = noaccum + ? (noaccum = false, value) + : callback(accumulator, value, index, collection) + }); + } + return accumulator; } - }); - - /** - * Boils down a `collection` to a single value. The initial state of the - * reduction is `accumulator` and each successive step of it should be returned - * by the `callback`. The `callback` is bound to `thisArg` and invoked with 4 - * arguments; for arrays they are (accumulator, value, index|key, collection). - * - * @static - * @memberOf _ - * @alias foldl, inject - * @category Collections - * @param {Array|Object|String} collection The collection to iterate over. - * @param {Function} callback The function called per iteration. - * @param {Mixed} [accumulator] Initial value of the accumulator. - * @param {Mixed} [thisArg] The `this` binding for the callback. - * @returns {Mixed} Returns the accumulated value. - * @example - * - * var sum = _.reduce([1, 2, 3], function(memo, num) { return memo + num; }); - * // => 6 - */ - var reduce = createIterator({ - 'args': 'collection, callback, accumulator, thisArg', - 'init': 'accumulator', - 'top': - 'var noaccum = arguments.length < 3;\n' + - 'if (thisArg) callback = iteratorBind(callback, thisArg)', - 'beforeLoop': { - 'array': 'if (noaccum) result = iteratee[++index]' - }, - 'inLoop': { - 'array': - 'result = callback(result, value, index, collection)', - 'object': - 'result = noaccum\n' + - ' ? (noaccum = false, value)\n' + - ' : callback(result, value, index, collection)' - } - }); - /** - * The right-associative version of `_.reduce`. - * - * @static - * @memberOf _ - * @alias foldr - * @category Collections - * @param {Array|Object|String} collection The collection to iterate over. - * @param {Function} callback The function called per iteration. - * @param {Mixed} [accumulator] Initial value of the accumulator. - * @param {Mixed} [thisArg] The `this` binding for the callback. - * @returns {Mixed} Returns the accumulated value. - * @example - * - * var list = [[0, 1], [2, 3], [4, 5]]; - * var flat = _.reduceRight(list, function(a, b) { return a.concat(b); }, []); - * // => [4, 5, 2, 3, 0, 1] - */ - function reduceRight(collection, callback, accumulator, thisArg) { - if (!collection) { + /** + * This method is like `_.reduce` except that it iterates over elements + * of a `collection` from right to left. + * + * @static + * @memberOf _ + * @alias foldr + * @category Collections + * @param {Array|Object|string} collection The collection to iterate over. + * @param {Function} [callback=identity] The function called per iteration. + * @param {*} [accumulator] Initial value of the accumulator. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {*} Returns the accumulated value. + * @example + * + * var list = [[0, 1], [2, 3], [4, 5]]; + * var flat = _.reduceRight(list, function(a, b) { return a.concat(b); }, []); + * // => [4, 5, 2, 3, 0, 1] + */ + function reduceRight(collection, callback, accumulator, thisArg) { + var noaccum = arguments.length < 3; + callback = baseCreateCallback(callback, thisArg, 4); + forEachRight(collection, function(value, index, collection) { + accumulator = noaccum + ? (noaccum = false, value) + : callback(accumulator, value, index, collection); + }); return accumulator; } - var length = collection.length, - noaccum = arguments.length < 3; - - if(thisArg) { - callback = iteratorBind(callback, thisArg); + /** + * The opposite of `_.filter` this method returns the elements of a + * collection that the callback does **not** return truey for. + * + * If a property name is provided for `callback` the created "_.pluck" style + * callback will return the property value of the given element. + * + * If an object is provided for `callback` the created "_.where" style callback + * will return `true` for elements that have the properties of the given object, + * else `false`. + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|string} collection The collection to iterate over. + * @param {Function|Object|string} [callback=identity] The function called + * per iteration. If a property name or object is provided it will be used + * to create a "_.pluck" or "_.where" style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {Array} Returns a new array of elements that failed the callback check. + * @example + * + * var odds = _.reject([1, 2, 3, 4, 5, 6], function(num) { return num % 2 == 0; }); + * // => [1, 3, 5] + * + * var food = [ + * { 'name': 'apple', 'organic': false, 'type': 'fruit' }, + * { 'name': 'carrot', 'organic': true, 'type': 'vegetable' } + * ]; + * + * // using "_.pluck" callback shorthand + * _.reject(food, 'organic'); + * // => [{ 'name': 'apple', 'organic': false, 'type': 'fruit' }] + * + * // using "_.where" callback shorthand + * _.reject(food, { 'type': 'fruit' }); + * // => [{ 'name': 'carrot', 'organic': true, 'type': 'vegetable' }] + */ + function reject(collection, callback, thisArg) { + callback = lodash.createCallback(callback, thisArg, 3); + return filter(collection, function(value, index, collection) { + return !callback(value, index, collection); + }); } - // Opera 10.53-10.60 JITted `length >>> 0` returns the wrong value for negative numbers - if (length > -1 && length === length >>> 0) { - var iteratee = noCharByIndex && toString.call(collection) == stringClass - ? collection.split('') - : collection; - if (length && noaccum) { - accumulator = iteratee[--length]; + /** + * Retrieves a random element or `n` random elements from a collection. + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|string} collection The collection to sample. + * @param {number} [n] The number of elements to sample. + * @param- {Object} [guard] Allows working with functions, like `_.map`, + * without using their `key` and `object` arguments as sources. + * @returns {Array} Returns the random sample(s) of `collection`. + * @example + * + * _.sample([1, 2, 3, 4]); + * // => 2 + * + * _.sample([1, 2, 3, 4], 2); + * // => [3, 1] + */ + function sample(collection, n, guard) { + var length = collection ? collection.length : 0; + if (typeof length != 'number') { + collection = values(collection); + } else if (support.unindexedChars && isString(collection)) { + collection = collection.split(''); } - while (length--) { - accumulator = callback(accumulator, iteratee[length], length, collection); + if (n == null || guard) { + return collection ? collection[random(length - 1)] : undefined; } - return accumulator; + var result = shuffle(collection); + result.length = nativeMin(nativeMax(0, n), result.length); + return result; } - var prop, - props = keys(collection); - - length = props.length; - if (length && noaccum) { - accumulator = collection[props[--length]]; + /** + * Creates an array of shuffled values, using a version of the Fisher-Yates + * shuffle. See http://en.wikipedia.org/wiki/Fisher-Yates_shuffle. + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|string} collection The collection to shuffle. + * @returns {Array} Returns a new shuffled collection. + * @example + * + * _.shuffle([1, 2, 3, 4, 5, 6]); + * // => [4, 1, 6, 3, 5, 2] + */ + function shuffle(collection) { + var index = -1, + length = collection ? collection.length : 0, + result = Array(typeof length == 'number' ? length : 0); + + forEach(collection, function(value) { + var rand = random(++index); + result[index] = result[rand]; + result[rand] = value; + }); + return result; } - while (length--) { - prop = props[length]; - accumulator = callback(accumulator, collection[prop], prop, collection); + + /** + * Gets the size of the `collection` by returning `collection.length` for arrays + * and array-like objects or the number of own enumerable properties for objects. + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|string} collection The collection to inspect. + * @returns {number} Returns `collection.length` or number of own enumerable properties. + * @example + * + * _.size([1, 2]); + * // => 2 + * + * _.size({ 'one': 1, 'two': 2, 'three': 3 }); + * // => 3 + * + * _.size('curly'); + * // => 5 + */ + function size(collection) { + var length = collection ? collection.length : 0; + return typeof length == 'number' ? length : keys(collection).length; } - return accumulator; - } - /** - * The opposite of `_.filter`, this method returns the values of a - * `collection` that `callback` does **not** return truthy for. - * - * @static - * @memberOf _ - * @category Collections - * @param {Array|Object|String} collection The collection to iterate over. - * @param {Function} [callback=identity] The function called per iteration. - * @param {Mixed} [thisArg] The `this` binding for the callback. - * @returns {Array} Returns a new array of elements that did **not** pass the callback check. - * @example - * - * var odds = _.reject([1, 2, 3, 4, 5, 6], function(num) { return num % 2 == 0; }); - * // => [1, 3, 5] - */ - var reject = createIterator(baseIteratorOptions, filterIteratorOptions, { - 'inLoop': '!' + filterIteratorOptions.inLoop - }); + /** + * Checks if the callback returns a truey value for **any** element of a + * collection. The function returns as soon as it finds a passing value and + * does not iterate over the entire collection. The callback is bound to + * `thisArg` and invoked with three arguments; (value, index|key, collection). + * + * If a property name is provided for `callback` the created "_.pluck" style + * callback will return the property value of the given element. + * + * If an object is provided for `callback` the created "_.where" style callback + * will return `true` for elements that have the properties of the given object, + * else `false`. + * + * @static + * @memberOf _ + * @alias any + * @category Collections + * @param {Array|Object|string} collection The collection to iterate over. + * @param {Function|Object|string} [callback=identity] The function called + * per iteration. If a property name or object is provided it will be used + * to create a "_.pluck" or "_.where" style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {boolean} Returns `true` if any element passed the callback check, + * else `false`. + * @example + * + * _.some([null, 0, 'yes', false], Boolean); + * // => true + * + * var food = [ + * { 'name': 'apple', 'organic': false, 'type': 'fruit' }, + * { 'name': 'carrot', 'organic': true, 'type': 'vegetable' } + * ]; + * + * // using "_.pluck" callback shorthand + * _.some(food, 'organic'); + * // => true + * + * // using "_.where" callback shorthand + * _.some(food, { 'type': 'meat' }); + * // => false + */ + function some(collection, callback, thisArg) { + var result; + callback = lodash.createCallback(callback, thisArg, 3); - /** - * Gets the size of the `collection` by returning `collection.length` for arrays - * and array-like objects or the number of own enumerable properties for objects. - * - * @static - * @memberOf _ - * @category Collections - * @param {Array|Object|String} collection The collection to inspect. - * @returns {Number} Returns `collection.length` or number of own enumerable properties. - * @example - * - * _.size([1, 2]); - * // => 2 - * - * _.size({ 'one': 1, 'two': 2, 'three': 3 }); - * // => 3 - * - * _.size('curly'); - * // => 5 - */ - function size(collection) { - if (!collection) { - return 0; - } - var length = collection.length; - return length > -1 && length === length >>> 0 ? length : keys(collection).length; - } + if (isArray(collection)) { + var index = -1, + length = collection.length; - /** - * Checks if the `callback` returns a truthy value for **any** element of a - * `collection`. The function returns as soon as it finds passing value, and - * does not iterate over the entire `collection`. The `callback` is bound to - * `thisArg` and invoked with 3 arguments; (value, index|key, collection). - * - * @static - * @memberOf _ - * @alias any - * @category Collections - * @param {Array|Object|String} collection The collection to iterate over. - * @param {Function} [callback=identity] The function called per iteration. - * @param {Mixed} [thisArg] The `this` binding for the callback. - * @returns {Boolean} Returns `true` if any element passes the callback check, else `false`. - * @example - * - * _.some([null, 0, 'yes', false]); - * // => true - */ - var some = createIterator(baseIteratorOptions, everyIteratorOptions, { - 'init': 'false', - 'inLoop': everyIteratorOptions.inLoop.replace('!', '') - }); + while (++index < length) { + if ((result = callback(collection[index], index, collection))) { + break; + } + } + } else { + baseEach(collection, function(value, index, collection) { + return !(result = callback(value, index, collection)); + }); + } + return !!result; + } - /** - * Creates a new array, stable sorted in ascending order by the results of - * running each element of `collection` through a `callback`. The `callback` - * is bound to `thisArg` and invoked with 3 arguments; (value, index|key, collection). - * The `callback` argument may also be the name of a property to sort by (e.g. 'length'). - * - * @static - * @memberOf _ - * @category Collections - * @param {Array|Object|String} collection The collection to iterate over. - * @param {Function|String} callback|property The function called per iteration - * or property name to sort by. - * @param {Mixed} [thisArg] The `this` binding for the callback. - * @returns {Array} Returns a new array of sorted elements. - * @example - * - * _.sortBy([1, 2, 3], function(num) { return Math.sin(num); }); - * // => [3, 1, 2] - * - * _.sortBy([1, 2, 3], function(num) { return this.sin(num); }, Math); - * // => [3, 1, 2] - * - * _.sortBy(['larry', 'brendan', 'moe'], 'length'); - * // => ['moe', 'larry', 'brendan'] - */ - var sortBy = createIterator(baseIteratorOptions, countByIteratorOptions, mapIteratorOptions, { - 'inLoop': { - 'array': - 'result[index] = {\n' + - ' criteria: callback(value, index, collection),\n' + - ' index: index,\n' + - ' value: value\n' + - '}', - 'object': - 'result' + (isKeysFast ? '[ownIndex] = ' : '.push') + '({\n' + - ' criteria: callback(value, index, collection),\n' + - ' index: index,\n' + - ' value: value\n' + - '})' - }, - 'bottom': - 'result.sort(compareAscending);\n' + - 'length = result.length;\n' + - 'while (length--) {\n' + - ' result[length] = result[length].value\n' + - '}' - }); + /** + * Creates an array of elements, sorted in ascending order by the results of + * running each element in a collection through the callback. This method + * performs a stable sort, that is, it will preserve the original sort order + * of equal elements. The callback is bound to `thisArg` and invoked with + * three arguments; (value, index|key, collection). + * + * If a property name is provided for `callback` the created "_.pluck" style + * callback will return the property value of the given element. + * + * If an object is provided for `callback` the created "_.where" style callback + * will return `true` for elements that have the properties of the given object, + * else `false`. + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|string} collection The collection to iterate over. + * @param {Function|Object|string} [callback=identity] The function called + * per iteration. If a property name or object is provided it will be used + * to create a "_.pluck" or "_.where" style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {Array} Returns a new array of sorted elements. + * @example + * + * _.sortBy([1, 2, 3], function(num) { return Math.sin(num); }); + * // => [3, 1, 2] + * + * _.sortBy([1, 2, 3], function(num) { return this.sin(num); }, Math); + * // => [3, 1, 2] + * + * // using "_.pluck" callback shorthand + * _.sortBy(['banana', 'strawberry', 'apple'], 'length'); + * // => ['apple', 'banana', 'strawberry'] + */ + function sortBy(collection, callback, thisArg) { + var index = -1, + length = collection ? collection.length : 0, + result = Array(typeof length == 'number' ? length : 0); + + callback = lodash.createCallback(callback, thisArg, 3); + forEach(collection, function(value, key, collection) { + var object = result[++index] = getObject(); + object.criteria = callback(value, key, collection); + object.index = index; + object.value = value; + }); - /** - * Converts the `collection`, to an array. Useful for converting the - * `arguments` object. - * - * @static - * @memberOf _ - * @category Collections - * @param {Array|Object|String} collection The collection to convert. - * @returns {Array} Returns the new converted array. - * @example - * - * (function() { return _.toArray(arguments).slice(1); })(1, 2, 3, 4); - * // => [2, 3, 4] - */ - function toArray(collection) { - if (!collection) { - return []; + length = result.length; + result.sort(compareAscending); + while (length--) { + var object = result[length]; + result[length] = object.value; + releaseObject(object); + } + return result; } - if (collection.toArray && isFunction(collection.toArray)) { - return collection.toArray(); + + /** + * Converts the `collection` to an array. + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|string} collection The collection to convert. + * @returns {Array} Returns the new converted array. + * @example + * + * (function() { return _.toArray(arguments).slice(1); })(1, 2, 3, 4); + * // => [2, 3, 4] + */ + function toArray(collection) { + if (collection && typeof collection.length == 'number') { + return (support.unindexedChars && isString(collection)) + ? collection.split('') + : slice(collection); + } + return values(collection); } - var length = collection.length; - if (length > -1 && length === length >>> 0) { - return (noArraySliceOnStrings ? toString.call(collection) == stringClass : typeof collection == 'string') - ? collection.split('') - : slice.call(collection); + + /** + * Performs a deep comparison of each element in a `collection` to the given + * `properties` object, returning an array of all elements that have equivalent + * property values. + * + * @static + * @memberOf _ + * @type Function + * @category Collections + * @param {Array|Object|string} collection The collection to iterate over. + * @param {Object} properties The object of property values to filter by. + * @returns {Array} Returns a new array of elements that have the given properties. + * @example + * + * var stooges = [ + * { 'name': 'curly', 'age': 30, 'quotes': ['Oh, a wise guy, eh?', 'Poifect!'] }, + * { 'name': 'moe', 'age': 40, 'quotes': ['Spread out!', 'You knucklehead!'] } + * ]; + * + * _.where(stooges, { 'age': 40 }); + * // => [{ 'name': 'moe', 'age': 40, 'quotes': ['Spread out!', 'You knucklehead!'] }] + * + * _.where(stooges, { 'quotes': ['Poifect!'] }); + * // => [{ 'name': 'curly', 'age': 30, 'quotes': ['Oh, a wise guy, eh?', 'Poifect!'] }] + */ + var where = filter; + + /*--------------------------------------------------------------------------*/ + + /** + * Creates an array with all falsey values removed. The values `false`, `null`, + * `0`, `""`, `undefined`, and `NaN` are all falsey. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} array The array to compact. + * @returns {Array} Returns a new array of filtered values. + * @example + * + * _.compact([0, 1, false, 2, '', 3]); + * // => [1, 2, 3] + */ + function compact(array) { + var index = -1, + length = array ? array.length : 0, + result = []; + + while (++index < length) { + var value = array[index]; + if (value) { + result.push(value); + } + } + return result; } - return values(collection); - } - /** - * Examines each element in a `collection`, returning an array of all elements - * that contain the given `properties`. - * - * @static - * @memberOf _ - * @category Collections - * @param {Array|Object|String} collection The collection to iterate over. - * @param {Object} properties The object of properties/values to filter by. - * @returns {Array} Returns a new array of elements that contain the given `properties`. - * @example - * - * var stooges = [ - * { 'name': 'moe', 'age': 40 }, - * { 'name': 'larry', 'age': 50 }, - * { 'name': 'curly', 'age': 60 } - * ]; - * - * _.where(stooges, { 'age': 40 }); - * // => [{ 'name': 'moe', 'age': 40 }] - */ - var where = createIterator(filterIteratorOptions, { - 'args': 'collection, properties', - 'top': - 'var props = [];\n' + - 'forIn(properties, function(value, prop) { props.push(prop) });\n' + - 'var propsLength = props.length', - 'inLoop': - 'for (var prop, pass = true, propIndex = 0; propIndex < propsLength; propIndex++) {\n' + - ' prop = props[propIndex];\n' + - ' if (!(pass = value[prop] === properties[prop])) break\n' + - '}\n' + - 'pass && result.push(value)' - }); + /** + * Creates an array excluding all values of the provided arrays using strict + * equality for comparisons, i.e. `===`. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} array The array to process. + * @param {...Array} [array] The arrays of values to exclude. + * @returns {Array} Returns a new array of filtered values. + * @example + * + * _.difference([1, 2, 3, 4, 5], [5, 2, 10]); + * // => [1, 3, 4] + */ + function difference(array) { + var index = -1, + indexOf = getIndexOf(), + length = array ? array.length : 0, + seen = baseFlatten(arguments, true, true, 1), + result = []; - /*--------------------------------------------------------------------------*/ + var isLarge = length >= largeArraySize && indexOf === baseIndexOf; - /** - * Creates a new array with all falsey values of `array` removed. The values - * `false`, `null`, `0`, `""`, `undefined` and `NaN` are all falsey. - * - * @static - * @memberOf _ - * @category Arrays - * @param {Array} array The array to compact. - * @returns {Array} Returns a new filtered array. - * @example - * - * _.compact([0, 1, false, 2, '', 3]); - * // => [1, 2, 3] - */ - function compact(array) { - var result = []; - if (!array) { + if (isLarge) { + var cache = createCache(seen); + if (cache) { + indexOf = cacheIndexOf; + seen = cache; + } else { + isLarge = false; + } + } + while (++index < length) { + var value = array[index]; + if (indexOf(seen, value) < 0) { + result.push(value); + } + } + if (isLarge) { + releaseObject(seen); + } return result; } - var index = -1, - length = array.length; - while (++index < length) { - if (array[index]) { - result.push(array[index]); + /** + * This method is like `_.find` except that it returns the index of the first + * element that passes the callback check, instead of the element itself. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} array The array to search. + * @param {Function|Object|string} [callback=identity] The function called + * per iteration. If a property name or object is provided it will be used + * to create a "_.pluck" or "_.where" style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {number} Returns the index of the found element, else `-1`. + * @example + * + * _.findIndex(['apple', 'banana', 'beet'], function(food) { + * return /^b/.test(food); + * }); + * // => 1 + */ + function findIndex(array, callback, thisArg) { + var index = -1, + length = array ? array.length : 0; + + callback = lodash.createCallback(callback, thisArg, 3); + while (++index < length) { + if (callback(array[index], index, array)) { + return index; + } + } + return -1; + } + + /** + * This method is like `_.findIndex` except that it iterates over elements + * of a `collection` from right to left. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} array The array to search. + * @param {Function|Object|string} [callback=identity] The function called + * per iteration. If a property name or object is provided it will be used + * to create a "_.pluck" or "_.where" style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {number} Returns the index of the found element, else `-1`. + * @example + * + * _.findLastIndex(['apple', 'banana', 'beet'], function(food) { + * return /^b/.test(food); + * }); + * // => 2 + */ + function findLastIndex(array, callback, thisArg) { + var length = array ? array.length : 0; + callback = lodash.createCallback(callback, thisArg, 3); + while (length--) { + if (callback(array[length], length, array)) { + return length; + } + } + return -1; + } + + /** + * Gets the first element or first `n` elements of an array. If a callback + * is provided elements at the beginning of the array are returned as long + * as the callback returns truey. The callback is bound to `thisArg` and + * invoked with three arguments; (value, index, array). + * + * If a property name is provided for `callback` the created "_.pluck" style + * callback will return the property value of the given element. + * + * If an object is provided for `callback` the created "_.where" style callback + * will return `true` for elements that have the properties of the given object, + * else `false`. + * + * @static + * @memberOf _ + * @alias head, take + * @category Arrays + * @param {Array} array The array to query. + * @param {Function|Object|number|string} [callback] The function called + * per element or the number of elements to return. If a property name or + * object is provided it will be used to create a "_.pluck" or "_.where" + * style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {*} Returns the first element(s) of `array`. + * @example + * + * _.first([1, 2, 3]); + * // => 1 + * + * _.first([1, 2, 3], 2); + * // => [1, 2] + * + * _.first([1, 2, 3], function(num) { + * return num < 3; + * }); + * // => [1, 2] + * + * var food = [ + * { 'name': 'banana', 'organic': true }, + * { 'name': 'beet', 'organic': false }, + * ]; + * + * // using "_.pluck" callback shorthand + * _.first(food, 'organic'); + * // => [{ 'name': 'banana', 'organic': true }] + * + * var food = [ + * { 'name': 'apple', 'type': 'fruit' }, + * { 'name': 'banana', 'type': 'fruit' }, + * { 'name': 'beet', 'type': 'vegetable' } + * ]; + * + * // using "_.where" callback shorthand + * _.first(food, { 'type': 'fruit' }); + * // => [{ 'name': 'apple', 'type': 'fruit' }, { 'name': 'banana', 'type': 'fruit' }] + */ + function first(array, callback, thisArg) { + var n = 0, + length = array ? array.length : 0; + + if (typeof callback != 'number' && callback != null) { + var index = -1; + callback = lodash.createCallback(callback, thisArg, 3); + while (++index < length && callback(array[index], index, array)) { + n++; + } + } else { + n = callback; + if (n == null || thisArg) { + return array ? array[0] : undefined; + } } + return slice(array, 0, nativeMin(nativeMax(0, n), length)); } - return result; - } - /** - * Creates a new array of `array` elements not present in the other arrays - * using strict equality for comparisons, i.e. `===`. - * - * @static - * @memberOf _ - * @category Arrays - * @param {Array} array The array to process. - * @param {Array} [array1, array2, ...] Arrays to check. - * @returns {Array} Returns a new array of `array` elements not present in the - * other arrays. - * @example - * - * _.difference([1, 2, 3, 4, 5], [5, 2, 10]); - * // => [1, 3, 4] - */ - function difference(array) { - var result = []; - if (!array) { - return result; + /** + * Flattens a nested array (the nesting can be to any depth). If `isShallow` + * is truey, the array will only be flattened a single level. If a callback + * is provided each element of the array is passed through the callback before + * flattening. The callback is bound to `thisArg` and invoked with three + * arguments; (value, index, array). + * + * If a property name is provided for `callback` the created "_.pluck" style + * callback will return the property value of the given element. + * + * If an object is provided for `callback` the created "_.where" style callback + * will return `true` for elements that have the properties of the given object, + * else `false`. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} array The array to flatten. + * @param {boolean} [isShallow=false] A flag to restrict flattening to a single level. + * @param {Function|Object|string} [callback=identity] The function called + * per iteration. If a property name or object is provided it will be used + * to create a "_.pluck" or "_.where" style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {Array} Returns a new flattened array. + * @example + * + * _.flatten([1, [2], [3, [[4]]]]); + * // => [1, 2, 3, 4]; + * + * _.flatten([1, [2], [3, [[4]]]], true); + * // => [1, 2, 3, [[4]]]; + * + * var stooges = [ + * { 'name': 'curly', 'quotes': ['Oh, a wise guy, eh?', 'Poifect!'] }, + * { 'name': 'moe', 'quotes': ['Spread out!', 'You knucklehead!'] } + * ]; + * + * // using "_.pluck" callback shorthand + * _.flatten(stooges, 'quotes'); + * // => ['Oh, a wise guy, eh?', 'Poifect!', 'Spread out!', 'You knucklehead!'] + */ + function flatten(array, isShallow, callback, thisArg) { + // juggle arguments + if (typeof isShallow != 'boolean' && isShallow != null) { + thisArg = callback; + callback = !(thisArg && thisArg[isShallow] === array) ? isShallow : null; + isShallow = false; + } + if (callback != null) { + array = map(array, callback, thisArg); + } + return baseFlatten(array, isShallow); } - var index = -1, - length = array.length, - flattened = concat.apply(result, arguments), - contains = cachedContains(flattened, length); - while (++index < length) { - if (!contains(array[index])) { - result.push(array[index]); + /** + * Gets the index at which the first occurrence of `value` is found using + * strict equality for comparisons, i.e. `===`. If the array is already sorted + * providing `true` for `fromIndex` will run a faster binary search. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} array The array to search. + * @param {*} value The value to search for. + * @param {boolean|number} [fromIndex=0] The index to search from or `true` + * to perform a binary search on a sorted array. + * @returns {number} Returns the index of the matched value or `-1`. + * @example + * + * _.indexOf([1, 2, 3, 1, 2, 3], 2); + * // => 1 + * + * _.indexOf([1, 2, 3, 1, 2, 3], 2, 3); + * // => 4 + * + * _.indexOf([1, 1, 2, 2, 3, 3], 2, true); + * // => 2 + */ + function indexOf(array, value, fromIndex) { + if (typeof fromIndex == 'number') { + var length = array ? array.length : 0; + fromIndex = (fromIndex < 0 ? nativeMax(0, length + fromIndex) : fromIndex || 0); + } else if (fromIndex) { + var index = sortedIndex(array, value); + return array[index] === value ? index : -1; } + return baseIndexOf(array, value, fromIndex); } - return result; - } - /** - * Gets the first element of the `array`. Pass `n` to return the first `n` - * elements of the `array`. - * - * @static - * @memberOf _ - * @alias head, take - * @category Arrays - * @param {Array} array The array to query. - * @param {Number} [n] The number of elements to return. - * @param {Object} [guard] Internally used to allow this method to work with - * others like `_.map` without using their callback `index` argument for `n`. - * @returns {Mixed} Returns the first element or an array of the first `n` - * elements of `array`. - * @example - * - * _.first([5, 4, 3, 2, 1]); - * // => 5 - */ - function first(array, n, guard) { - if (array) { - return (n == null || guard) ? array[0] : slice.call(array, 0, n); + /** + * Gets all but the last element or last `n` elements of an array. If a + * callback is provided elements at the end of the array are excluded from + * the result as long as the callback returns truey. The callback is bound + * to `thisArg` and invoked with three arguments; (value, index, array). + * + * If a property name is provided for `callback` the created "_.pluck" style + * callback will return the property value of the given element. + * + * If an object is provided for `callback` the created "_.where" style callback + * will return `true` for elements that have the properties of the given object, + * else `false`. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} array The array to query. + * @param {Function|Object|number|string} [callback=1] The function called + * per element or the number of elements to exclude. If a property name or + * object is provided it will be used to create a "_.pluck" or "_.where" + * style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {Array} Returns a slice of `array`. + * @example + * + * _.initial([1, 2, 3]); + * // => [1, 2] + * + * _.initial([1, 2, 3], 2); + * // => [1] + * + * _.initial([1, 2, 3], function(num) { + * return num > 1; + * }); + * // => [1] + * + * var food = [ + * { 'name': 'beet', 'organic': false }, + * { 'name': 'carrot', 'organic': true } + * ]; + * + * // using "_.pluck" callback shorthand + * _.initial(food, 'organic'); + * // => [{ 'name': 'beet', 'organic': false }] + * + * var food = [ + * { 'name': 'banana', 'type': 'fruit' }, + * { 'name': 'beet', 'type': 'vegetable' }, + * { 'name': 'carrot', 'type': 'vegetable' } + * ]; + * + * // using "_.where" callback shorthand + * _.initial(food, { 'type': 'vegetable' }); + * // => [{ 'name': 'banana', 'type': 'fruit' }] + */ + function initial(array, callback, thisArg) { + var n = 0, + length = array ? array.length : 0; + + if (typeof callback != 'number' && callback != null) { + var index = length; + callback = lodash.createCallback(callback, thisArg, 3); + while (index-- && callback(array[index], index, array)) { + n++; + } + } else { + n = (callback == null || thisArg) ? 1 : callback || n; + } + return slice(array, 0, nativeMin(nativeMax(0, length - n), length)); } - } - /** - * Flattens a nested array (the nesting can be to any depth). If `shallow` is - * truthy, `array` will only be flattened a single level. - * - * @static - * @memberOf _ - * @category Arrays - * @param {Array} array The array to compact. - * @param {Boolean} shallow A flag to indicate only flattening a single level. - * @returns {Array} Returns a new flattened array. - * @example - * - * _.flatten([1, [2], [3, [[4]]]]); - * // => [1, 2, 3, 4]; - * - * _.flatten([1, [2], [3, [[4]]]], true); - * // => [1, 2, 3, [[4]]]; - */ - function flatten(array, shallow) { - var result = []; - if (!array) { + /** + * Creates an array of unique values present in all provided arrays using + * strict equality for comparisons, i.e. `===`. + * + * @static + * @memberOf _ + * @category Arrays + * @param {...Array} [array] The arrays to inspect. + * @returns {Array} Returns an array of composite values. + * @example + * + * _.intersection([1, 2, 3], [101, 2, 1, 10], [2, 1]); + * // => [1, 2] + */ + function intersection(array) { + var args = arguments, + argsLength = args.length, + argsIndex = -1, + caches = getArray(), + index = -1, + indexOf = getIndexOf(), + length = array ? array.length : 0, + result = [], + seen = getArray(); + + while (++argsIndex < argsLength) { + var value = args[argsIndex]; + caches[argsIndex] = indexOf === baseIndexOf && + (value ? value.length : 0) >= largeArraySize && + createCache(argsIndex ? args[argsIndex] : seen); + } + outer: + while (++index < length) { + var cache = caches[0]; + value = array[index]; + + if ((cache ? cacheIndexOf(cache, value) : indexOf(seen, value)) < 0) { + argsIndex = argsLength; + (cache || seen).push(value); + while (--argsIndex) { + cache = caches[argsIndex]; + if ((cache ? cacheIndexOf(cache, value) : indexOf(args[argsIndex], value)) < 0) { + continue outer; + } + } + result.push(value); + } + } + while (argsLength--) { + cache = caches[argsLength]; + if (cache) { + releaseObject(cache); + } + } + releaseArray(caches); + releaseArray(seen); return result; } - var value, - index = -1, - length = array.length; - while (++index < length) { - value = array[index]; - if (isArray(value)) { - push.apply(result, shallow ? value : flatten(value)); + /** + * Gets the last element or last `n` elements of an array. If a callback is + * provided elements at the end of the array are returned as long as the + * callback returns truey. The callback is bound to `thisArg` and invoked + * with three arguments; (value, index, array). + * + * If a property name is provided for `callback` the created "_.pluck" style + * callback will return the property value of the given element. + * + * If an object is provided for `callback` the created "_.where" style callback + * will return `true` for elements that have the properties of the given object, + * else `false`. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} array The array to query. + * @param {Function|Object|number|string} [callback] The function called + * per element or the number of elements to return. If a property name or + * object is provided it will be used to create a "_.pluck" or "_.where" + * style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {*} Returns the last element(s) of `array`. + * @example + * + * _.last([1, 2, 3]); + * // => 3 + * + * _.last([1, 2, 3], 2); + * // => [2, 3] + * + * _.last([1, 2, 3], function(num) { + * return num > 1; + * }); + * // => [2, 3] + * + * var food = [ + * { 'name': 'beet', 'organic': false }, + * { 'name': 'carrot', 'organic': true } + * ]; + * + * // using "_.pluck" callback shorthand + * _.last(food, 'organic'); + * // => [{ 'name': 'carrot', 'organic': true }] + * + * var food = [ + * { 'name': 'banana', 'type': 'fruit' }, + * { 'name': 'beet', 'type': 'vegetable' }, + * { 'name': 'carrot', 'type': 'vegetable' } + * ]; + * + * // using "_.where" callback shorthand + * _.last(food, { 'type': 'vegetable' }); + * // => [{ 'name': 'beet', 'type': 'vegetable' }, { 'name': 'carrot', 'type': 'vegetable' }] + */ + function last(array, callback, thisArg) { + var n = 0, + length = array ? array.length : 0; + + if (typeof callback != 'number' && callback != null) { + var index = length; + callback = lodash.createCallback(callback, thisArg, 3); + while (index-- && callback(array[index], index, array)) { + n++; + } } else { - result.push(value); + n = callback; + if (n == null || thisArg) { + return array ? array[length - 1] : undefined; + } } + return slice(array, nativeMax(0, length - n)); } - return result; - } - - /** - * Gets the index at which the first occurrence of `value` is found using - * strict equality for comparisons, i.e. `===`. If the `array` is already - * sorted, passing `true` for `isSorted` will run a faster binary search. - * - * @static - * @memberOf _ - * @category Arrays - * @param {Array} array The array to search. - * @param {Mixed} value The value to search for. - * @param {Boolean|Number} [fromIndex=0] The index to start searching from or - * `true` to perform a binary search on a sorted `array`. - * @returns {Number} Returns the index of the matched value or `-1`. - * @example - * - * _.indexOf([1, 2, 3, 1, 2, 3], 2); - * // => 1 - * - * _.indexOf([1, 2, 3, 1, 2, 3], 2, 3); - * // => 4 - * - * _.indexOf([1, 1, 2, 2, 3, 3], 2, true); - * // => 2 - */ - function indexOf(array, value, fromIndex) { - if (!array) { - return -1; - } - var index = -1, - length = array.length; - if (fromIndex) { + /** + * Gets the index at which the last occurrence of `value` is found using strict + * equality for comparisons, i.e. `===`. If `fromIndex` is negative, it is used + * as the offset from the end of the collection. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} array The array to search. + * @param {*} value The value to search for. + * @param {number} [fromIndex=array.length-1] The index to search from. + * @returns {number} Returns the index of the matched value or `-1`. + * @example + * + * _.lastIndexOf([1, 2, 3, 1, 2, 3], 2); + * // => 4 + * + * _.lastIndexOf([1, 2, 3, 1, 2, 3], 2, 3); + * // => 1 + */ + function lastIndexOf(array, value, fromIndex) { + var index = array ? array.length : 0; if (typeof fromIndex == 'number') { - index = (fromIndex < 0 ? nativeMax(0, length + fromIndex) : fromIndex) - 1; - } else { - index = sortedIndex(array, value); - return array[index] === value ? index : -1; + index = (fromIndex < 0 ? nativeMax(0, index + fromIndex) : nativeMin(fromIndex, index - 1)) + 1; } - } - while (++index < length) { - if (array[index] === value) { - return index; + while (index--) { + if (array[index] === value) { + return index; + } } + return -1; } - return -1; - } - - /** - * Gets all but the last element of `array`. Pass `n` to exclude the last `n` - * elements from the result. - * - * @static - * @memberOf _ - * @category Arrays - * @param {Array} array The array to query. - * @param {Number} [n] The number of elements to return. - * @param {Object} [guard] Internally used to allow this method to work with - * others like `_.map` without using their callback `index` argument for `n`. - * @returns {Array} Returns all but the last element or `n` elements of `array`. - * @example - * - * _.initial([3, 2, 1]); - * // => [3, 2] - */ - function initial(array, n, guard) { - if (!array) { - return []; - } - return slice.call(array, 0, -((n == null || guard) ? 1 : n)); - } - /** - * Computes the intersection of all the passed-in arrays using strict equality - * for comparisons, i.e. `===`. - * - * @static - * @memberOf _ - * @category Arrays - * @param {Array} [array1, array2, ...] Arrays to process. - * @returns {Array} Returns a new array of unique elements, in order, that are - * present in **all** of the arrays. - * @example - * - * _.intersection([1, 2, 3], [101, 2, 1, 10], [2, 1]); - * // => [1, 2] - */ - function intersection(array) { - var result = []; - if (!array) { - return result; - } - var value, - argsLength = arguments.length, - cache = [], - index = -1, - length = array.length; - - array: while (++index < length) { - value = array[index]; - if (indexOf(result, value) < 0) { - for (var argsIndex = 1; argsIndex < argsLength; argsIndex++) { - if (!(cache[argsIndex] || (cache[argsIndex] = cachedContains(arguments[argsIndex])))(value)) { - continue array; + /** + * Removes all provided values from the given array using strict equality for + * comparisons, i.e. `===`. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} array The array to modify. + * @param {...*} [value] The values to remove. + * @returns {Array} Returns `array`. + * @example + * + * var array = [1, 2, 3, 1, 2, 3]; + * _.pull(array, 2, 3); + * console.log(array); + * // => [1, 1] + */ + function pull(array) { + var args = arguments, + argsIndex = 0, + argsLength = args.length, + length = array ? array.length : 0; + + while (++argsIndex < argsLength) { + var index = -1, + value = args[argsIndex]; + while (++index < length) { + if (array[index] === value) { + splice.call(array, index--, 1); + length--; } } - result.push(value); } + return array; } - return result; - } - /** - * Gets the last element of the `array`. Pass `n` to return the lasy `n` - * elementsvof the `array`. - * - * @static - * @memberOf _ - * @category Arrays - * @param {Array} array The array to query. - * @param {Number} [n] The number of elements to return. - * @param {Object} [guard] Internally used to allow this method to work with - * others like `_.map` without using their callback `index` argument for `n`. - * @returns {Mixed} Returns the last element or an array of the last `n` - * elements of `array`. - * @example - * - * _.last([3, 2, 1]); - * // => 1 - */ - function last(array, n, guard) { - if (array) { - var length = array.length; - return (n == null || guard) ? array[length - 1] : slice.call(array, -n || length); - } - } + /** + * Creates an array of numbers (positive and/or negative) progressing from + * `start` up to but not including `end`. If `start` is less than `stop` a + * zero-length range is created unless a negative `step` is specified. + * + * @static + * @memberOf _ + * @category Arrays + * @param {number} [start=0] The start of the range. + * @param {number} end The end of the range. + * @param {number} [step=1] The value to increment or decrement by. + * @returns {Array} Returns a new range array. + * @example + * + * _.range(10); + * // => [0, 1, 2, 3, 4, 5, 6, 7, 8, 9] + * + * _.range(1, 11); + * // => [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] + * + * _.range(0, 30, 5); + * // => [0, 5, 10, 15, 20, 25] + * + * _.range(0, -10, -1); + * // => [0, -1, -2, -3, -4, -5, -6, -7, -8, -9] + * + * _.range(1, 4, 0); + * // => [1, 1, 1] + * + * _.range(0); + * // => [] + */ + function range(start, end, step) { + start = +start || 0; + step = typeof step == 'number' ? step : (+step || 1); - /** - * Gets the index at which the last occurrence of `value` is found using - * strict equality for comparisons, i.e. `===`. - * - * @static - * @memberOf _ - * @category Arrays - * @param {Array} array The array to search. - * @param {Mixed} value The value to search for. - * @param {Number} [fromIndex=array.length-1] The index to start searching from. - * @returns {Number} Returns the index of the matched value or `-1`. - * @example - * - * _.lastIndexOf([1, 2, 3, 1, 2, 3], 2); - * // => 4 - * - * _.lastIndexOf([1, 2, 3, 1, 2, 3], 2, 3); - * // => 1 - */ - function lastIndexOf(array, value, fromIndex) { - if (!array) { - return -1; - } - var index = array.length; - if (fromIndex && typeof fromIndex == 'number') { - index = (fromIndex < 0 ? nativeMax(0, index + fromIndex) : nativeMin(fromIndex, index - 1)) + 1; - } - while (index--) { - if (array[index] === value) { - return index; + if (end == null) { + end = start; + start = 0; + } + // use `Array(length)` so engines, like Chakra and V8, avoid slower modes + // http://youtu.be/XAqIpGU8ZZk#t=17m25s + var index = -1, + length = nativeMax(0, ceil((end - start) / (step || 1))), + result = Array(length); + + while (++index < length) { + result[index] = start; + start += step; } + return result; } - return -1; - } - /** - * Retrieves the maximum value of an `array`. If `callback` is passed, - * it will be executed for each value in the `array` to generate the - * criterion by which the value is ranked. The `callback` is bound to - * `thisArg` and invoked with 3 arguments; (value, index, array). - * - * @static - * @memberOf _ - * @category Arrays - * @param {Array} array The array to iterate over. - * @param {Function} [callback] The function called per iteration. - * @param {Mixed} [thisArg] The `this` binding for the callback. - * @returns {Mixed} Returns the maximum value. - * @example - * - * var stooges = [ - * { 'name': 'moe', 'age': 40 }, - * { 'name': 'larry', 'age': 50 }, - * { 'name': 'curly', 'age': 60 } - * ]; - * - * _.max(stooges, function(stooge) { return stooge.age; }); - * // => { 'name': 'curly', 'age': 60 }; - */ - function max(array, callback, thisArg) { - var computed = -Infinity, - result = computed; + /** + * Removes all elements from an array that the callback returns truey for + * and returns an array of removed elements. The callback is bound to `thisArg` + * and invoked with three arguments; (value, index, array). + * + * If a property name is provided for `callback` the created "_.pluck" style + * callback will return the property value of the given element. + * + * If an object is provided for `callback` the created "_.where" style callback + * will return `true` for elements that have the properties of the given object, + * else `false`. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} array The array to modify. + * @param {Function|Object|string} [callback=identity] The function called + * per iteration. If a property name or object is provided it will be used + * to create a "_.pluck" or "_.where" style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {Array} Returns a new array of removed elements. + * @example + * + * var array = [1, 2, 3, 4, 5, 6]; + * var evens = _.remove(array, function(num) { return num % 2 == 0; }); + * + * console.log(array); + * // => [1, 3, 5] + * + * console.log(evens); + * // => [2, 4, 6] + */ + function remove(array, callback, thisArg) { + var index = -1, + length = array ? array.length : 0, + result = []; - if (!array) { + callback = lodash.createCallback(callback, thisArg, 3); + while (++index < length) { + var value = array[index]; + if (callback(value, index, array)) { + result.push(value); + splice.call(array, index--, 1); + length--; + } + } return result; } - var current, - index = -1, - length = array.length; - if (!callback) { - while (++index < length) { - if (array[index] > result) { - result = array[index]; - } + /** + * The opposite of `_.initial` this method gets all but the first element or + * first `n` elements of an array. If a callback function is provided elements + * at the beginning of the array are excluded from the result as long as the + * callback returns truey. The callback is bound to `thisArg` and invoked + * with three arguments; (value, index, array). + * + * If a property name is provided for `callback` the created "_.pluck" style + * callback will return the property value of the given element. + * + * If an object is provided for `callback` the created "_.where" style callback + * will return `true` for elements that have the properties of the given object, + * else `false`. + * + * @static + * @memberOf _ + * @alias drop, tail + * @category Arrays + * @param {Array} array The array to query. + * @param {Function|Object|number|string} [callback=1] The function called + * per element or the number of elements to exclude. If a property name or + * object is provided it will be used to create a "_.pluck" or "_.where" + * style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {Array} Returns a slice of `array`. + * @example + * + * _.rest([1, 2, 3]); + * // => [2, 3] + * + * _.rest([1, 2, 3], 2); + * // => [3] + * + * _.rest([1, 2, 3], function(num) { + * return num < 3; + * }); + * // => [3] + * + * var food = [ + * { 'name': 'banana', 'organic': true }, + * { 'name': 'beet', 'organic': false }, + * ]; + * + * // using "_.pluck" callback shorthand + * _.rest(food, 'organic'); + * // => [{ 'name': 'beet', 'organic': false }] + * + * var food = [ + * { 'name': 'apple', 'type': 'fruit' }, + * { 'name': 'banana', 'type': 'fruit' }, + * { 'name': 'beet', 'type': 'vegetable' } + * ]; + * + * // using "_.where" callback shorthand + * _.rest(food, { 'type': 'fruit' }); + * // => [{ 'name': 'beet', 'type': 'vegetable' }] + */ + function rest(array, callback, thisArg) { + if (typeof callback != 'number' && callback != null) { + var n = 0, + index = -1, + length = array ? array.length : 0; + + callback = lodash.createCallback(callback, thisArg, 3); + while (++index < length && callback(array[index], index, array)) { + n++; + } + } else { + n = (callback == null || thisArg) ? 1 : nativeMax(0, callback); + } + return slice(array, n); + } + + /** + * Uses a binary search to determine the smallest index at which a value + * should be inserted into a given sorted array in order to maintain the sort + * order of the array. If a callback is provided it will be executed for + * `value` and each element of `array` to compute their sort ranking. The + * callback is bound to `thisArg` and invoked with one argument; (value). + * + * If a property name is provided for `callback` the created "_.pluck" style + * callback will return the property value of the given element. + * + * If an object is provided for `callback` the created "_.where" style callback + * will return `true` for elements that have the properties of the given object, + * else `false`. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} array The array to inspect. + * @param {*} value The value to evaluate. + * @param {Function|Object|string} [callback=identity] The function called + * per iteration. If a property name or object is provided it will be used + * to create a "_.pluck" or "_.where" style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {number} Returns the index at which `value` should be inserted + * into `array`. + * @example + * + * _.sortedIndex([20, 30, 50], 40); + * // => 2 + * + * // using "_.pluck" callback shorthand + * _.sortedIndex([{ 'x': 20 }, { 'x': 30 }, { 'x': 50 }], { 'x': 40 }, 'x'); + * // => 2 + * + * var dict = { + * 'wordToNumber': { 'twenty': 20, 'thirty': 30, 'fourty': 40, 'fifty': 50 } + * }; + * + * _.sortedIndex(['twenty', 'thirty', 'fifty'], 'fourty', function(word) { + * return dict.wordToNumber[word]; + * }); + * // => 2 + * + * _.sortedIndex(['twenty', 'thirty', 'fifty'], 'fourty', function(word) { + * return this.wordToNumber[word]; + * }, dict); + * // => 2 + */ + function sortedIndex(array, value, callback, thisArg) { + var low = 0, + high = array ? array.length : low; + + // explicitly reference `identity` for better inlining in Firefox + callback = callback ? lodash.createCallback(callback, thisArg, 1) : identity; + value = callback(value); + + while (low < high) { + var mid = (low + high) >>> 1; + (callback(array[mid]) < value) + ? low = mid + 1 + : high = mid; } - return result; + return low; } - if (thisArg) { - callback = iteratorBind(callback, thisArg); + + /** + * Creates an array of unique values, in order, of the provided arrays using + * strict equality for comparisons, i.e. `===`. + * + * @static + * @memberOf _ + * @category Arrays + * @param {...Array} [array] The arrays to inspect. + * @returns {Array} Returns an array of composite values. + * @example + * + * _.union([1, 2, 3], [101, 2, 1, 10], [2, 1]); + * // => [1, 2, 3, 101, 10] + */ + function union(array) { + return baseUniq(baseFlatten(arguments, true, true)); } - while (++index < length) { - current = callback(array[index], index, array); - if (current > computed) { - computed = current; - result = array[index]; + + /** + * Creates a duplicate-value-free version of an array using strict equality + * for comparisons, i.e. `===`. If the array is sorted, providing + * `true` for `isSorted` will use a faster algorithm. If a callback is provided + * each element of `array` is passed through the callback before uniqueness + * is computed. The callback is bound to `thisArg` and invoked with three + * arguments; (value, index, array). + * + * If a property name is provided for `callback` the created "_.pluck" style + * callback will return the property value of the given element. + * + * If an object is provided for `callback` the created "_.where" style callback + * will return `true` for elements that have the properties of the given object, + * else `false`. + * + * @static + * @memberOf _ + * @alias unique + * @category Arrays + * @param {Array} array The array to process. + * @param {boolean} [isSorted=false] A flag to indicate that `array` is sorted. + * @param {Function|Object|string} [callback=identity] The function called + * per iteration. If a property name or object is provided it will be used + * to create a "_.pluck" or "_.where" style callback, respectively. + * @param {*} [thisArg] The `this` binding of `callback`. + * @returns {Array} Returns a duplicate-value-free array. + * @example + * + * _.uniq([1, 2, 1, 3, 1]); + * // => [1, 2, 3] + * + * _.uniq([1, 1, 2, 2, 3], true); + * // => [1, 2, 3] + * + * _.uniq(['A', 'b', 'C', 'a', 'B', 'c'], function(letter) { return letter.toLowerCase(); }); + * // => ['A', 'b', 'C'] + * + * _.uniq([1, 2.5, 3, 1.5, 2, 3.5], function(num) { return this.floor(num); }, Math); + * // => [1, 2.5, 3] + * + * // using "_.pluck" callback shorthand + * _.uniq([{ 'x': 1 }, { 'x': 2 }, { 'x': 1 }], 'x'); + * // => [{ 'x': 1 }, { 'x': 2 }] + */ + function uniq(array, isSorted, callback, thisArg) { + // juggle arguments + if (typeof isSorted != 'boolean' && isSorted != null) { + thisArg = callback; + callback = !(thisArg && thisArg[isSorted] === array) ? isSorted : null; + isSorted = false; + } + if (callback != null) { + callback = lodash.createCallback(callback, thisArg, 3); } + return baseUniq(array, isSorted, callback); } - return result; - } - /** - * Retrieves the minimum value of an `array`. If `callback` is passed, - * it will be executed for each value in the `array` to generate the - * criterion by which the value is ranked. The `callback` is bound to `thisArg` - * and invoked with 3 arguments; (value, index, array). - * - * @static - * @memberOf _ - * @category Arrays - * @param {Array} array The array to iterate over. - * @param {Function} [callback] The function called per iteration. - * @param {Mixed} [thisArg] The `this` binding for the callback. - * @returns {Mixed} Returns the minimum value. - * @example - * - * _.min([10, 5, 100, 2, 1000]); - * // => 2 - */ - function min(array, callback, thisArg) { - var computed = Infinity, - result = computed; + /** + * Creates an array excluding all provided values using strict equality for + * comparisons, i.e. `===`. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} array The array to filter. + * @param {...*} [value] The values to exclude. + * @returns {Array} Returns a new array of filtered values. + * @example + * + * _.without([1, 2, 1, 0, 3, 1, 4], 0, 1); + * // => [2, 3, 4] + */ + function without(array) { + return difference(array, nativeSlice.call(arguments, 1)); + } + + /** + * Creates an array of grouped elements, the first of which contains the first + * elements of the given arrays, the second of which contains the second + * elements of the given arrays, and so on. + * + * @static + * @memberOf _ + * @alias unzip + * @category Arrays + * @param {...Array} [array] Arrays to process. + * @returns {Array} Returns a new array of grouped elements. + * @example + * + * _.zip(['moe', 'larry'], [30, 40], [true, false]); + * // => [['moe', 30, true], ['larry', 40, false]] + */ + function zip() { + var array = arguments.length > 1 ? arguments : arguments[0], + index = -1, + length = array ? max(pluck(array, 'length')) : 0, + result = Array(length < 0 ? 0 : length); - if (!array) { + while (++index < length) { + result[index] = pluck(array, index); + } return result; } - var current, - index = -1, - length = array.length; - if (!callback) { + /** + * Creates an object composed from arrays of `keys` and `values`. Provide + * either a single two dimensional array, i.e. `[[key1, value1], [key2, value2]]` + * or two arrays, one of `keys` and one of corresponding `values`. + * + * @static + * @memberOf _ + * @alias object + * @category Arrays + * @param {Array} keys The array of keys. + * @param {Array} [values=[]] The array of values. + * @returns {Object} Returns an object composed of the given keys and + * corresponding values. + * @example + * + * _.zipObject(['moe', 'larry'], [30, 40]); + * // => { 'moe': 30, 'larry': 40 } + */ + function zipObject(keys, values) { + var index = -1, + length = keys ? keys.length : 0, + result = {}; + while (++index < length) { - if (array[index] < result) { - result = array[index]; + var key = keys[index]; + if (values) { + result[key] = values[index]; + } else if (key) { + result[key[0]] = key[1]; } } return result; } - if (thisArg) { - callback = iteratorBind(callback, thisArg); - } - while (++index < length) { - current = callback(array[index], index, array); - if (current < computed) { - computed = current; - result = array[index]; - } - } - return result; - } - /** - * Creates an object composed from arrays of `keys` and `values`. Pass either - * a single two dimensional array, i.e. `[[key1, value1], [key2, value2]]`, or - * two arrays, one of `keys` and one of corresponding `values`. - * - * @static - * @memberOf _ - * @category Arrays - * @param {Array} keys The array of keys. - * @param {Array} [values=[]] The array of values. - * @returns {Object} Returns an object composed of the given keys and - * corresponding values. - * @example - * - * _.object(['moe', 'larry', 'curly'], [30, 40, 50]); - * // => { 'moe': 30, 'larry': 40, 'curly': 50 } - */ - function object(keys, values) { - if (!keys) { - return {}; - } - var index = -1, - length = keys.length, - result = {}; + /*--------------------------------------------------------------------------*/ - while (++index < length) { - if (values) { - result[keys[index]] = values[index]; - } else { - result[keys[index][0]] = keys[index][1]; + /** + * Creates a function that executes `func`, with the `this` binding and + * arguments of the created function, only after being called `n` times. + * + * @static + * @memberOf _ + * @category Functions + * @param {number} n The number of times the function must be called before + * `func` is executed. + * @param {Function} func The function to restrict. + * @returns {Function} Returns the new restricted function. + * @example + * + * var saves = ['profile', 'settings']; + * + * var done = _.after(saves.length, function() { + * console.log('Done saving!'); + * }); + * + * _.forEach(saves, function(type) { + * asyncSave({ 'type': type, 'complete': done }); + * }); + * // => logs 'Done saving!', after all saves have completed + */ + function after(n, func) { + if (!isFunction(func)) { + throw new TypeError; } + return function() { + if (--n < 1) { + return func.apply(this, arguments); + } + }; } - return result; - } - - /** - * Creates an array of numbers (positive and/or negative) progressing from - * `start` up to but not including `stop`. This method is a port of Python's - * `range()` function. See http://docs.python.org/library/functions.html#range. - * - * @static - * @memberOf _ - * @category Arrays - * @param {Number} [start=0] The start of the range. - * @param {Number} end The end of the range. - * @param {Number} [step=1] The value to increment or descrement by. - * @returns {Array} Returns a new range array. - * @example - * - * _.range(10); - * // => [0, 1, 2, 3, 4, 5, 6, 7, 8, 9] - * - * _.range(1, 11); - * // => [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] - * - * _.range(0, 30, 5); - * // => [0, 5, 10, 15, 20, 25] - * - * _.range(0, -10, -1); - * // => [0, -1, -2, -3, -4, -5, -6, -7, -8, -9] - * - * _.range(0); - * // => [] - */ - function range(start, end, step) { - start = +start || 0; - step = +step || 1; - if (end == null) { - end = start; - start = 0; + /** + * Creates a function that, when called, invokes `func` with the `this` + * binding of `thisArg` and prepends any additional `bind` arguments to those + * provided to the bound function. + * + * @static + * @memberOf _ + * @category Functions + * @param {Function} func The function to bind. + * @param {*} [thisArg] The `this` binding of `func`. + * @param {...*} [arg] Arguments to be partially applied. + * @returns {Function} Returns the new bound function. + * @example + * + * var func = function(greeting) { + * return greeting + ' ' + this.name; + * }; + * + * func = _.bind(func, { 'name': 'moe' }, 'hi'); + * func(); + * // => 'hi moe' + */ + function bind(func, thisArg) { + return arguments.length > 2 + ? createBound(func, 17, nativeSlice.call(arguments, 2), null, thisArg) + : createBound(func, 1, null, null, thisArg); } - // use `Array(length)` so V8 will avoid the slower "dictionary" mode - // http://www.youtube.com/watch?v=XAqIpGU8ZZk#t=16m27s - var index = -1, - length = nativeMax(0, Math.ceil((end - start) / step)), - result = Array(length); - while (++index < length) { - result[index] = start; - start += step; - } - return result; - } + /** + * Binds methods of an object to the object itself, overwriting the existing + * method. Method names may be specified as individual arguments or as arrays + * of method names. If no method names are provided all the function properties + * of `object` will be bound. + * + * @static + * @memberOf _ + * @category Functions + * @param {Object} object The object to bind and assign the bound methods to. + * @param {...string} [methodName] The object method names to + * bind, specified as individual method names or arrays of method names. + * @returns {Object} Returns `object`. + * @example + * + * var view = { + * 'label': 'docs', + * 'onClick': function() { console.log('clicked ' + this.label); } + * }; + * + * _.bindAll(view); + * jQuery('#docs').on('click', view.onClick); + * // => logs 'clicked docs', when the button is clicked + */ + function bindAll(object) { + var funcs = arguments.length > 1 ? baseFlatten(arguments, true, false, 1) : functions(object), + index = -1, + length = funcs.length; - /** - * The opposite of `_.initial`, this method gets all but the first value of - * `array`. Pass `n` to exclude the first `n` values from the result. - * - * @static - * @memberOf _ - * @alias drop, tail - * @category Arrays - * @param {Array} array The array to query. - * @param {Number} [n] The number of elements to return. - * @param {Object} [guard] Internally used to allow this method to work with - * others like `_.map` without using their callback `index` argument for `n`. - * @returns {Array} Returns all but the first value or `n` values of `array`. - * @example - * - * _.rest([3, 2, 1]); - * // => [2, 1] - */ - function rest(array, n, guard) { - if (!array) { - return []; + while (++index < length) { + var key = funcs[index]; + object[key] = createBound(object[key], 1, null, null, object); + } + return object; } - return slice.call(array, (n == null || guard) ? 1 : n); - } - /** - * Creates a new array of shuffled `array` values, using a version of the - * Fisher-Yates shuffle. See http://en.wikipedia.org/wiki/Fisher-Yates_shuffle. - * - * @static - * @memberOf _ - * @category Arrays - * @param {Array} array The array to shuffle. - * @returns {Array} Returns a new shuffled array. - * @example - * - * _.shuffle([1, 2, 3, 4, 5, 6]); - * // => [4, 1, 6, 3, 5, 2] - */ - function shuffle(array) { - if (!array) { - return []; + /** + * Creates a function that, when called, invokes the method at `object[key]` + * and prepends any additional `bindKey` arguments to those provided to the bound + * function. This method differs from `_.bind` by allowing bound functions to + * reference methods that will be redefined or don't yet exist. + * See http://michaux.ca/articles/lazy-function-definition-pattern. + * + * @static + * @memberOf _ + * @category Functions + * @param {Object} object The object the method belongs to. + * @param {string} key The key of the method. + * @param {...*} [arg] Arguments to be partially applied. + * @returns {Function} Returns the new bound function. + * @example + * + * var object = { + * 'name': 'moe', + * 'greet': function(greeting) { + * return greeting + ' ' + this.name; + * } + * }; + * + * var func = _.bindKey(object, 'greet', 'hi'); + * func(); + * // => 'hi moe' + * + * object.greet = function(greeting) { + * return greeting + ', ' + this.name + '!'; + * }; + * + * func(); + * // => 'hi, moe!' + */ + function bindKey(object, key) { + return arguments.length > 2 + ? createBound(key, 19, nativeSlice.call(arguments, 2), null, object) + : createBound(key, 3, null, null, object); } - var rand, - index = -1, - length = array.length, - result = Array(length); - while (++index < length) { - rand = nativeFloor(nativeRandom() * (index + 1)); - result[index] = result[rand]; - result[rand] = array[index]; - } - return result; - } + /** + * Creates a function that is the composition of the provided functions, + * where each function consumes the return value of the function that follows. + * For example, composing the functions `f()`, `g()`, and `h()` produces `f(g(h()))`. + * Each function is executed with the `this` binding of the composed function. + * + * @static + * @memberOf _ + * @category Functions + * @param {...Function} [func] Functions to compose. + * @returns {Function} Returns the new composed function. + * @example + * + * var realNameMap = { + * 'curly': 'jerome' + * }; + * + * var format = function(name) { + * name = realNameMap[name.toLowerCase()] || name; + * return name.charAt(0).toUpperCase() + name.slice(1).toLowerCase(); + * }; + * + * var greet = function(formatted) { + * return 'Hiya ' + formatted + '!'; + * }; + * + * var welcome = _.compose(greet, format); + * welcome('curly'); + * // => 'Hiya Jerome!' + */ + function compose() { + var funcs = arguments, + length = funcs.length; - /** - * Uses a binary search to determine the smallest index at which the `value` - * should be inserted into `array` in order to maintain the sort order of the - * sorted `array`. If `callback` is passed, it will be executed for `value` and - * each element in `array` to compute their sort ranking. The `callback` is - * bound to `thisArg` and invoked with 1 argument; (value). - * - * @static - * @memberOf _ - * @category Arrays - * @param {Array} array The array to iterate over. - * @param {Mixed} value The value to evaluate. - * @param {Function} [callback=identity] The function called per iteration. - * @param {Mixed} [thisArg] The `this` binding for the callback. - * @returns {Number} Returns the index at which the value should be inserted - * into `array`. - * @example - * - * _.sortedIndex([20, 30, 40], 35); - * // => 2 - * - * var dict = { - * 'wordToNumber': { 'twenty': 20, 'thirty': 30, 'thirty-five': 35, 'fourty': 40 } - * }; - * - * _.sortedIndex(['twenty', 'thirty', 'fourty'], 'thirty-five', function(word) { - * return dict.wordToNumber[word]; - * }); - * // => 2 - * - * _.sortedIndex(['twenty', 'thirty', 'fourty'], 'thirty-five', function(word) { - * return this.wordToNumber[word]; - * }, dict); - * // => 2 - */ - function sortedIndex(array, value, callback, thisArg) { - if (!array) { - return 0; + while (length--) { + if (!isFunction(funcs[length])) { + throw new TypeError; + } + } + return function() { + var args = arguments, + length = funcs.length; + + while (length--) { + args = [funcs[length].apply(this, args)]; + } + return args[0]; + }; } - var mid, - low = 0, - high = array.length; - if (callback) { - if (thisArg) { - callback = bind(callback, thisArg); + /** + * Produces a callback bound to an optional `thisArg`. If `func` is a property + * name the created callback will return the property value for a given element. + * If `func` is an object the created callback will return `true` for elements + * that contain the equivalent object properties, otherwise it will return `false`. + * + * @static + * @memberOf _ + * @category Functions + * @param {*} [func=identity] The value to convert to a callback. + * @param {*} [thisArg] The `this` binding of the created callback. + * @param {number} [argCount] The number of arguments the callback accepts. + * @returns {Function} Returns a callback function. + * @example + * + * var stooges = [ + * { 'name': 'moe', 'age': 40 }, + * { 'name': 'larry', 'age': 50 } + * ]; + * + * // wrap to create custom callback shorthands + * _.createCallback = _.wrap(_.createCallback, function(func, callback, thisArg) { + * var match = /^(.+?)__([gl]t)(.+)$/.exec(callback); + * return !match ? func(callback, thisArg) : function(object) { + * return match[2] == 'gt' ? object[match[1]] > match[3] : object[match[1]] < match[3]; + * }; + * }); + * + * _.filter(stooges, 'age__gt45'); + * // => [{ 'name': 'larry', 'age': 50 }] + */ + function createCallback(func, thisArg, argCount) { + var type = typeof func; + if (func == null || type == 'function') { + return baseCreateCallback(func, thisArg, argCount); } - value = callback(value); - while (low < high) { - mid = (low + high) >>> 1; - callback(array[mid]) < value ? low = mid + 1 : high = mid; + // handle "_.pluck" style callback shorthands + if (type != 'object') { + return function(object) { + return object[func]; + }; } - } else { - while (low < high) { - mid = (low + high) >>> 1; - array[mid] < value ? low = mid + 1 : high = mid; + var props = keys(func), + key = props[0], + a = func[key]; + + // handle "_.where" style callback shorthands + if (props.length == 1 && a === a && !isObject(a)) { + // fast path the common case of providing an object with a single + // property containing a primitive value + return function(object) { + var b = object[key]; + return a === b && (a !== 0 || (1 / a == 1 / b)); + }; } + return function(object) { + var length = props.length, + result = false; + + while (length--) { + if (!(result = baseIsEqual(object[props[length]], func[props[length]], null, true))) { + break; + } + } + return result; + }; } - return low; - } - /** - * Computes the union of the passed-in arrays using strict equality for - * comparisons, i.e. `===`. - * - * @static - * @memberOf _ - * @category Arrays - * @param {Array} [array1, array2, ...] Arrays to process. - * @returns {Array} Returns a new array of unique values, in order, that are - * present in one or more of the arrays. - * @example - * - * _.union([1, 2, 3], [101, 2, 1, 10], [2, 1]); - * // => [1, 2, 3, 101, 10] - */ - function union() { - var index = -1, - result = [], - flattened = concat.apply(result, arguments), - length = flattened.length; + /** + * Creates a function which accepts one or more arguments of `func` that when + * invoked either executes `func` returning its result, if all `func` arguments + * have been provided, or returns a function that accepts one or more of the + * remaining `func` arguments, and so on. The arity of `func` can be specified + * if `func.length` is not sufficient. + * + * @static + * @memberOf _ + * @category Functions + * @param {Function} func The function to curry. + * @param {number} [arity=func.length] The arity of `func`. + * @returns {Function} Returns the new curried function. + * @example + * + * var curried = _.curry(function(a, b, c) { + * console.log(a + b + c); + * }); + * + * curried(1)(2)(3); + * // => 6 + * + * curried(1, 2)(3); + * // => 6 + * + * curried(1, 2, 3); + * // => 6 + */ + function curry(func, arity) { + arity = typeof arity == 'number' ? arity : (+arity || func.length); + return createBound(func, 4, null, null, null, arity); + } - while (++index < length) { - if (indexOf(result, flattened[index]) < 0) { - result.push(flattened[index]); + /** + * Creates a function that will delay the execution of `func` until after + * `wait` milliseconds have elapsed since the last time it was invoked. + * Provide an options object to indicate that `func` should be invoked on + * the leading and/or trailing edge of the `wait` timeout. Subsequent calls + * to the debounced function will return the result of the last `func` call. + * + * Note: If `leading` and `trailing` options are `true` `func` will be called + * on the trailing edge of the timeout only if the the debounced function is + * invoked more than once during the `wait` timeout. + * + * @static + * @memberOf _ + * @category Functions + * @param {Function} func The function to debounce. + * @param {number} wait The number of milliseconds to delay. + * @param {Object} [options] The options object. + * @param {boolean} [options.leading=false] Specify execution on the leading edge of the timeout. + * @param {number} [options.maxWait] The maximum time `func` is allowed to be delayed before it's called. + * @param {boolean} [options.trailing=true] Specify execution on the trailing edge of the timeout. + * @returns {Function} Returns the new debounced function. + * @example + * + * // avoid costly calculations while the window size is in flux + * var lazyLayout = _.debounce(calculateLayout, 150); + * jQuery(window).on('resize', lazyLayout); + * + * // execute `sendMail` when the click event is fired, debouncing subsequent calls + * jQuery('#postbox').on('click', _.debounce(sendMail, 300, { + * 'leading': true, + * 'trailing': false + * }); + * + * // ensure `batchLog` is executed once after 1 second of debounced calls + * var source = new EventSource('/stream'); + * source.addEventListener('message', _.debounce(batchLog, 250, { + * 'maxWait': 1000 + * }, false); + */ + function debounce(func, wait, options) { + var args, + maxTimeoutId, + result, + stamp, + thisArg, + timeoutId, + trailingCall, + lastCalled = 0, + maxWait = false, + trailing = true; + + if (!isFunction(func)) { + throw new TypeError; } - } - return result; - } + wait = nativeMax(0, wait) || 0; + if (options === true) { + var leading = true; + trailing = false; + } else if (isObject(options)) { + leading = options.leading; + maxWait = 'maxWait' in options && (nativeMax(wait, options.maxWait) || 0); + trailing = 'trailing' in options ? options.trailing : trailing; + } + var delayed = function() { + var remaining = wait - (now() - stamp); + if (remaining <= 0) { + if (maxTimeoutId) { + clearTimeout(maxTimeoutId); + } + var isCalled = trailingCall; + maxTimeoutId = timeoutId = trailingCall = undefined; + if (isCalled) { + lastCalled = now(); + result = func.apply(thisArg, args); + } + } else { + timeoutId = setTimeout(delayed, remaining); + } + }; - /** - * Creates a duplicate-value-free version of the `array` using strict equality - * for comparisons, i.e. `===`. If the `array` is already sorted, passing `true` - * for `isSorted` will run a faster algorithm. If `callback` is passed, each - * element of `array` is passed through a callback` before uniqueness is computed. - * The `callback` is bound to `thisArg` and invoked with 3 arguments; (value, index, array). - * - * @static - * @memberOf _ - * @alias unique - * @category Arrays - * @param {Array} array The array to process. - * @param {Boolean} [isSorted=false] A flag to indicate that the `array` is already sorted. - * @param {Function} [callback=identity] The function called per iteration. - * @param {Mixed} [thisArg] The `this` binding for the callback. - * @returns {Array} Returns a duplicate-value-free array. - * @example - * - * _.uniq([1, 2, 1, 3, 1]); - * // => [1, 2, 3] - * - * _.uniq([1, 1, 2, 2, 3], true); - * // => [1, 2, 3] - * - * _.uniq([1, 2, 1.5, 3, 2.5], function(num) { return Math.floor(num); }); - * // => [1, 2, 3] - * - * _.uniq([1, 2, 1.5, 3, 2.5], function(num) { return this.floor(num); }, Math); - * // => [1, 2, 3] - */ - function uniq(array, isSorted, callback, thisArg) { - var result = []; - if (!array) { - return result; - } - var computed, - index = -1, - length = array.length, - seen = []; + var maxDelayed = function() { + if (timeoutId) { + clearTimeout(timeoutId); + } + maxTimeoutId = timeoutId = trailingCall = undefined; + if (trailing || (maxWait !== wait)) { + lastCalled = now(); + result = func.apply(thisArg, args); + } + }; - // juggle arguments - if (typeof isSorted == 'function') { - thisArg = callback; - callback = isSorted; - isSorted = false; - } - if (!callback) { - callback = identity; - } else if (thisArg) { - callback = iteratorBind(callback, thisArg); + return function() { + args = arguments; + stamp = now(); + thisArg = this; + trailingCall = trailing && (timeoutId || !leading); + + if (maxWait === false) { + var leadingCall = leading && !timeoutId; + } else { + if (!maxTimeoutId && !leading) { + lastCalled = stamp; + } + var remaining = maxWait - (stamp - lastCalled); + if (remaining <= 0) { + if (maxTimeoutId) { + maxTimeoutId = clearTimeout(maxTimeoutId); + } + lastCalled = stamp; + result = func.apply(thisArg, args); + } + else if (!maxTimeoutId) { + maxTimeoutId = setTimeout(maxDelayed, remaining); + } + } + if (!timeoutId && wait !== maxWait) { + timeoutId = setTimeout(delayed, wait); + } + if (leadingCall) { + result = func.apply(thisArg, args); + } + return result; + }; } - while (++index < length) { - computed = callback(array[index], index, array); - if (isSorted - ? !index || seen[seen.length - 1] !== computed - : indexOf(seen, computed) < 0 - ) { - seen.push(computed); - result.push(array[index]); + + /** + * Defers executing the `func` function until the current call stack has cleared. + * Additional arguments will be provided to `func` when it is invoked. + * + * @static + * @memberOf _ + * @category Functions + * @param {Function} func The function to defer. + * @param {...*} [arg] Arguments to invoke the function with. + * @returns {number} Returns the timer id. + * @example + * + * _.defer(function() { console.log('deferred'); }); + * // returns from the function before 'deferred' is logged + */ + function defer(func) { + if (!isFunction(func)) { + throw new TypeError; } + var args = nativeSlice.call(arguments, 1); + return setTimeout(function() { func.apply(undefined, args); }, 1); } - return result; - } - - /** - * Creates a new array with all occurrences of the passed values removed using - * strict equality for comparisons, i.e. `===`. - * - * @static - * @memberOf _ - * @category Arrays - * @param {Array} array The array to filter. - * @param {Mixed} [value1, value2, ...] Values to remove. - * @returns {Array} Returns a new filtered array. - * @example - * - * _.without([1, 2, 1, 0, 3, 1, 4], 0, 1); - * // => [2, 3, 4] - */ - function without(array) { - var result = []; - if (!array) { - return result; + // use `setImmediate` if available in Node.js + if (isV8 && moduleExports && typeof setImmediate == 'function') { + defer = function(func) { + if (!isFunction(func)) { + throw new TypeError; + } + return setImmediate.apply(context, arguments); + }; } - var index = -1, - length = array.length, - contains = cachedContains(arguments, 1, 20); - while (++index < length) { - if (!contains(array[index])) { - result.push(array[index]); + /** + * Executes the `func` function after `wait` milliseconds. Additional arguments + * will be provided to `func` when it is invoked. + * + * @static + * @memberOf _ + * @category Functions + * @param {Function} func The function to delay. + * @param {number} wait The number of milliseconds to delay execution. + * @param {...*} [arg] Arguments to invoke the function with. + * @returns {number} Returns the timer id. + * @example + * + * var log = _.bind(console.log, console); + * _.delay(log, 1000, 'logged later'); + * // => 'logged later' (Appears after one second.) + */ + function delay(func, wait) { + if (!isFunction(func)) { + throw new TypeError; } + var args = nativeSlice.call(arguments, 2); + return setTimeout(function() { func.apply(undefined, args); }, wait); } - return result; - } - /** - * Groups the elements of each array at their corresponding indexes. Useful for - * separate data sources that are coordinated through matching array indexes. - * For a matrix of nested arrays, `_.zip.apply(...)` can transpose the matrix - * in a similar fashion. - * - * @static - * @memberOf _ - * @category Arrays - * @param {Array} [array1, array2, ...] Arrays to process. - * @returns {Array} Returns a new array of grouped elements. - * @example - * - * _.zip(['moe', 'larry', 'curly'], [30, 40, 50], [true, false, false]); - * // => [['moe', 30, true], ['larry', 40, false], ['curly', 50, false]] - */ - function zip(array) { - if (!array) { - return []; - } - var index = -1, - length = max(pluck(arguments, 'length')), - result = Array(length); + /** + * Creates a function that memoizes the result of `func`. If `resolver` is + * provided it will be used to determine the cache key for storing the result + * based on the arguments provided to the memoized function. By default, the + * first argument provided to the memoized function is used as the cache key. + * The `func` is executed with the `this` binding of the memoized function. + * The result cache is exposed as the `cache` property on the memoized function. + * + * @static + * @memberOf _ + * @category Functions + * @param {Function} func The function to have its output memoized. + * @param {Function} [resolver] A function used to resolve the cache key. + * @returns {Function} Returns the new memoizing function. + * @example + * + * var fibonacci = _.memoize(function(n) { + * return n < 2 ? n : fibonacci(n - 1) + fibonacci(n - 2); + * }); + * + * var data = { + * 'moe': { 'name': 'moe', 'age': 40 }, + * 'curly': { 'name': 'curly', 'age': 60 } + * }; + * + * // modifying the result cache + * var stooge = _.memoize(function(name) { return data[name]; }, _.identity); + * stooge('curly'); + * // => { 'name': 'curly', 'age': 60 } + * + * stooge.cache.curly.name = 'jerome'; + * stooge('curly'); + * // => { 'name': 'jerome', 'age': 60 } + */ + function memoize(func, resolver) { + if (!isFunction(func)) { + throw new TypeError; + } + var memoized = function() { + var cache = memoized.cache, + key = resolver ? resolver.apply(this, arguments) : keyPrefix + arguments[0]; - while (++index < length) { - result[index] = pluck(arguments, index); + return hasOwnProperty.call(cache, key) + ? cache[key] + : (cache[key] = func.apply(this, arguments)); + } + memoized.cache = {}; + return memoized; } - return result; - } - /*--------------------------------------------------------------------------*/ + /** + * Creates a function that is restricted to execute `func` once. Repeat calls to + * the function will return the value of the first call. The `func` is executed + * with the `this` binding of the created function. + * + * @static + * @memberOf _ + * @category Functions + * @param {Function} func The function to restrict. + * @returns {Function} Returns the new restricted function. + * @example + * + * var initialize = _.once(createApplication); + * initialize(); + * initialize(); + * // `initialize` executes `createApplication` once + */ + function once(func) { + var ran, + result; - /** - * Creates a new function that is restricted to executing only after it is - * called `n` times. - * - * @static - * @memberOf _ - * @category Functions - * @param {Number} n The number of times the function must be called before - * it is executed. - * @param {Function} func The function to restrict. - * @returns {Function} Returns the new restricted function. - * @example - * - * var renderNotes = _.after(notes.length, render); - * _.forEach(notes, function(note) { - * note.asyncSave({ 'success': renderNotes }); - * }); - * // `renderNotes` is run once, after all notes have saved - */ - function after(n, func) { - if (n < 1) { - return func(); - } - return function() { - if (--n < 1) { - return func.apply(this, arguments); + if (!isFunction(func)) { + throw new TypeError; } - }; - } - - /** - * Creates a new function that, when called, invokes `func` with the `this` - * binding of `thisArg` and prepends any additional `bind` arguments to those - * passed to the bound function. Lazy defined methods may be bound by passing - * the object they are bound to as `func` and the method name as `thisArg`. - * - * @static - * @memberOf _ - * @category Functions - * @param {Function|Object} func The function to bind or the object the method belongs to. - * @param {Mixed} [thisArg] The `this` binding of `func` or the method name. - * @param {Mixed} [arg1, arg2, ...] Arguments to be partially applied. - * @returns {Function} Returns the new bound function. - * @example - * - * // basic bind - * var func = function(greeting) { - * return greeting + ' ' + this.name; - * }; - * - * func = _.bind(func, { 'name': 'moe' }, 'hi'); - * func(); - * // => 'hi moe' - * - * // lazy bind - * var object = { - * 'name': 'moe', - * 'greet': function(greeting) { - * return greeting + ' ' + this.name; - * } - * }; - * - * var func = _.bind(object, 'greet', 'hi'); - * func(); - * // => 'hi moe' - * - * object.greet = function(greeting) { - * return greeting + ', ' + this.name + '!'; - * }; - * - * func(); - * // => 'hi, moe!' - */ - function bind(func, thisArg) { - var methodName, - isFunc = isFunction(func); + return function() { + if (ran) { + return result; + } + ran = true; + result = func.apply(this, arguments); - // juggle arguments - if (!isFunc) { - methodName = thisArg; - thisArg = func; + // clear the `func` variable so the function may be garbage collected + func = null; + return result; + }; } - // use `Function#bind` if it exists and is fast - // (in V8 `Function#bind` is slower except when partially applied) - else if (isBindFast || (nativeBind && arguments.length > 2)) { - return nativeBind.call.apply(nativeBind, arguments); + + /** + * Creates a function that, when called, invokes `func` with any additional + * `partial` arguments prepended to those provided to the new function. This + * method is similar to `_.bind` except it does **not** alter the `this` binding. + * + * @static + * @memberOf _ + * @category Functions + * @param {Function} func The function to partially apply arguments to. + * @param {...*} [arg] Arguments to be partially applied. + * @returns {Function} Returns the new partially applied function. + * @example + * + * var greet = function(greeting, name) { return greeting + ' ' + name; }; + * var hi = _.partial(greet, 'hi'); + * hi('moe'); + * // => 'hi moe' + */ + function partial(func) { + return createBound(func, 16, nativeSlice.call(arguments, 1)); } - var partialArgs = slice.call(arguments, 2); + /** + * This method is like `_.partial` except that `partial` arguments are + * appended to those provided to the new function. + * + * @static + * @memberOf _ + * @category Functions + * @param {Function} func The function to partially apply arguments to. + * @param {...*} [arg] Arguments to be partially applied. + * @returns {Function} Returns the new partially applied function. + * @example + * + * var defaultsDeep = _.partialRight(_.merge, _.defaults); + * + * var options = { + * 'variable': 'data', + * 'imports': { 'jq': $ } + * }; + * + * defaultsDeep(options, _.templateSettings); + * + * options.variable + * // => 'data' + * + * options.imports + * // => { '_': _, 'jq': $ } + */ + function partialRight(func) { + return createBound(func, 32, null, nativeSlice.call(arguments, 1)); + } - function bound() { - // `Function#bind` spec - // http://es5.github.com/#x15.3.4.5 - var args = arguments, - thisBinding = thisArg; + /** + * Creates a function that, when executed, will only call the `func` function + * at most once per every `wait` milliseconds. Provide an options object to + * indicate that `func` should be invoked on the leading and/or trailing edge + * of the `wait` timeout. Subsequent calls to the throttled function will + * return the result of the last `func` call. + * + * Note: If `leading` and `trailing` options are `true` `func` will be called + * on the trailing edge of the timeout only if the the throttled function is + * invoked more than once during the `wait` timeout. + * + * @static + * @memberOf _ + * @category Functions + * @param {Function} func The function to throttle. + * @param {number} wait The number of milliseconds to throttle executions to. + * @param {Object} [options] The options object. + * @param {boolean} [options.leading=true] Specify execution on the leading edge of the timeout. + * @param {boolean} [options.trailing=true] Specify execution on the trailing edge of the timeout. + * @returns {Function} Returns the new throttled function. + * @example + * + * // avoid excessively updating the position while scrolling + * var throttled = _.throttle(updatePosition, 100); + * jQuery(window).on('scroll', throttled); + * + * // execute `renewToken` when the click event is fired, but not more than once every 5 minutes + * jQuery('.interactive').on('click', _.throttle(renewToken, 300000, { + * 'trailing': false + * })); + */ + function throttle(func, wait, options) { + var leading = true, + trailing = true; - if (!isFunc) { - func = thisArg[methodName]; + if (!isFunction(func)) { + throw new TypeError; } - if (partialArgs.length) { - args = args.length - ? partialArgs.concat(slice.call(args)) - : partialArgs; + if (options === false) { + leading = false; + } else if (isObject(options)) { + leading = 'leading' in options ? options.leading : leading; + trailing = 'trailing' in options ? options.trailing : trailing; } - if (this instanceof bound) { - // get `func` instance if `bound` is invoked in a `new` expression - noop.prototype = func.prototype; - thisBinding = new noop; + debounceOptions.leading = leading; + debounceOptions.maxWait = wait; + debounceOptions.trailing = trailing; - // mimic the constructor's `return` behavior - // http://es5.github.com/#x13.2.2 - var result = func.apply(thisBinding, args); - return result && objectTypes[typeof result] - ? result - : thisBinding - } - return func.apply(thisBinding, args); + var result = debounce(func, wait, debounceOptions); + return result; } - return bound; - } - - /** - * Binds methods on `object` to `object`, overwriting the existing method. - * If no method names are provided, all the function properties of `object` - * will be bound. - * - * @static - * @memberOf _ - * @category Functions - * @param {Object} object The object to bind and assign the bound methods to. - * @param {String} [methodName1, methodName2, ...] Method names on the object to bind. - * @returns {Object} Returns `object`. - * @example - * - * var buttonView = { - * 'label': 'lodash', - * 'onClick': function() { alert('clicked: ' + this.label); } - * }; - * - * _.bindAll(buttonView); - * jQuery('#lodash_button').on('click', buttonView.onClick); - * // => When the button is clicked, `this.label` will have the correct value - */ - var bindAll = createIterator({ - 'useHas': false, - 'useStrict': false, - 'args': 'object', - 'init': 'object', - 'top': - 'var funcs = arguments,\n' + - ' length = funcs.length;\n' + - 'if (length > 1) {\n' + - ' for (var index = 1; index < length; index++) {\n' + - ' result[funcs[index]] = bind(result[funcs[index]], result)\n' + - ' }\n' + - ' return result\n' + - '}', - 'inLoop': - 'if (isFunction(result[index])) {\n' + - ' result[index] = bind(result[index], result)\n' + - '}' - }); - - /** - * Creates a new function that is the composition of the passed functions, - * where each function consumes the return value of the function that follows. - * In math terms, composing the functions `f()`, `g()`, and `h()` produces `f(g(h()))`. - * - * @static - * @memberOf _ - * @category Functions - * @param {Function} [func1, func2, ...] Functions to compose. - * @returns {Function} Returns the new composed function. - * @example - * - * var greet = function(name) { return 'hi: ' + name; }; - * var exclaim = function(statement) { return statement + '!'; }; - * var welcome = _.compose(exclaim, greet); - * welcome('moe'); - * // => 'hi: moe!' - */ - function compose() { - var funcs = arguments; - return function() { - var args = arguments, - length = funcs.length; - while (length--) { - args = [funcs[length].apply(this, args)]; + /** + * Creates a function that provides `value` to the wrapper function as its + * first argument. Additional arguments provided to the function are appended + * to those provided to the wrapper function. The wrapper is executed with + * the `this` binding of the created function. + * + * @static + * @memberOf _ + * @category Functions + * @param {*} value The value to wrap. + * @param {Function} wrapper The wrapper function. + * @returns {Function} Returns the new function. + * @example + * + * var hello = function(name) { return 'hello ' + name; }; + * hello = _.wrap(hello, function(func) { + * return 'before, ' + func('moe') + ', after'; + * }); + * hello(); + * // => 'before, hello moe, after' + */ + function wrap(value, wrapper) { + if (!isFunction(wrapper)) { + throw new TypeError; } - return args[0]; - }; - } + return function() { + var args = [value]; + push.apply(args, arguments); + return wrapper.apply(this, args); + }; + } - /** - * Creates a new function that will delay the execution of `func` until after - * `wait` milliseconds have elapsed since the last time it was invoked. Pass - * `true` for `immediate` to cause debounce to invoke `func` on the leading, - * instead of the trailing, edge of the `wait` timeout. Subsequent calls to - * the debounced function will return the result of the last `func` call. - * - * @static - * @memberOf _ - * @category Functions - * @param {Function} func The function to debounce. - * @param {Number} wait The number of milliseconds to delay. - * @param {Boolean} immediate A flag to indicate execution is on the leading - * edge of the timeout. - * @returns {Function} Returns the new debounced function. - * @example - * - * var lazyLayout = _.debounce(calculateLayout, 300); - * jQuery(window).on('resize', lazyLayout); - */ - function debounce(func, wait, immediate) { - var args, - result, - thisArg, - timeoutId; + /*--------------------------------------------------------------------------*/ - function delayed() { - timeoutId = null; - if (!immediate) { - result = func.apply(thisArg, args); - } + /** + * Converts the characters `&`, `<`, `>`, `"`, and `'` in `string` to their + * corresponding HTML entities. + * + * @static + * @memberOf _ + * @category Utilities + * @param {string} string The string to escape. + * @returns {string} Returns the escaped string. + * @example + * + * _.escape('Moe, Larry & Curly'); + * // => 'Moe, Larry & Curly' + */ + function escape(string) { + return string == null ? '' : String(string).replace(reUnescapedHtml, escapeHtmlChar); } - return function() { - var isImmediate = immediate && !timeoutId; - args = arguments; - thisArg = this; - - clearTimeout(timeoutId); - timeoutId = setTimeout(delayed, wait); + /** + * This method returns the first argument provided to it. + * + * @static + * @memberOf _ + * @category Utilities + * @param {*} value Any value. + * @returns {*} Returns `value`. + * @example + * + * var moe = { 'name': 'moe' }; + * moe === _.identity(moe); + * // => true + */ + function identity(value) { + return value; + } - if (isImmediate) { - result = func.apply(thisArg, args); + /** + * Adds function properties of a source object to the `lodash` function and + * chainable wrapper. + * + * @static + * @memberOf _ + * @category Utilities + * @param {Object} object The object of function properties to add to `lodash`. + * @param {Object} object The object of function properties to add to `lodash`. + * @example + * + * _.mixin({ + * 'capitalize': function(string) { + * return string.charAt(0).toUpperCase() + string.slice(1).toLowerCase(); + * } + * }); + * + * _.capitalize('moe'); + * // => 'Moe' + * + * _('moe').capitalize(); + * // => 'Moe' + */ + function mixin(object, source) { + var ctor = object, + isFunc = !source || isFunction(ctor); + + if (!source) { + ctor = lodashWrapper; + source = object; + object = lodash; } - return result; - }; - } - - /** - * Executes the `func` function after `wait` milliseconds. Additional arguments - * will be passed to `func` when it is invoked. - * - * @static - * @memberOf _ - * @category Functions - * @param {Function} func The function to delay. - * @param {Number} wait The number of milliseconds to delay execution. - * @param {Mixed} [arg1, arg2, ...] Arguments to invoke the function with. - * @returns {Number} Returns the `setTimeout` timeout id. - * @example - * - * var log = _.bind(console.log, console); - * _.delay(log, 1000, 'logged later'); - * // => 'logged later' (Appears after one second.) - */ - function delay(func, wait) { - var args = slice.call(arguments, 2); - return setTimeout(function() { return func.apply(undefined, args); }, wait); - } + forEach(functions(source), function(methodName) { + var func = object[methodName] = source[methodName]; + if (isFunc) { + ctor.prototype[methodName] = function() { + var value = this.__wrapped__, + args = [value]; + + push.apply(args, arguments); + var result = func.apply(object, args); + if (value && typeof value == 'object' && value === result) { + return this; + } + result = new ctor(result); + result.__chain__ = this.__chain__; + return result; + }; + } + }); + } - /** - * Defers executing the `func` function until the current call stack has cleared. - * Additional arguments will be passed to `func` when it is invoked. - * - * @static - * @memberOf _ - * @category Functions - * @param {Function} func The function to defer. - * @param {Mixed} [arg1, arg2, ...] Arguments to invoke the function with. - * @returns {Number} Returns the `setTimeout` timeout id. - * @example - * - * _.defer(function() { alert('deferred'); }); - * // returns from the function before `alert` is called - */ - function defer(func) { - var args = slice.call(arguments, 1); - return setTimeout(function() { return func.apply(undefined, args); }, 1); - } + /** + * Reverts the '_' variable to its previous value and returns a reference to + * the `lodash` function. + * + * @static + * @memberOf _ + * @category Utilities + * @returns {Function} Returns the `lodash` function. + * @example + * + * var lodash = _.noConflict(); + */ + function noConflict() { + context._ = oldDash; + return this; + } - /** - * Creates a new function that memoizes the result of `func`. If `resolver` is - * passed, it will be used to determine the cache key for storing the result - * based on the arguments passed to the memoized function. By default, the first - * argument passed to the memoized function is used as the cache key. - * - * @static - * @memberOf _ - * @category Functions - * @param {Function} func The function to have its output memoized. - * @param {Function} [resolver] A function used to resolve the cache key. - * @returns {Function} Returns the new memoizing function. - * @example - * - * var fibonacci = _.memoize(function(n) { - * return n < 2 ? n : fibonacci(n - 1) + fibonacci(n - 2); - * }); - */ - function memoize(func, resolver) { - var cache = {}; - return function() { - var prop = resolver ? resolver.apply(this, arguments) : arguments[0]; - return hasOwnProperty.call(cache, prop) - ? cache[prop] - : (cache[prop] = func.apply(this, arguments)); + /** + * Converts the given value into an integer of the specified radix. + * If `radix` is `undefined` or `0` a `radix` of `10` is used unless the + * `value` is a hexadecimal, in which case a `radix` of `16` is used. + * + * Note: This method avoids differences in native ES3 and ES5 `parseInt` + * implementations. See http://es5.github.io/#E. + * + * @static + * @memberOf _ + * @category Utilities + * @param {string} value The value to parse. + * @param {number} [radix] The radix used to interpret the value to parse. + * @returns {number} Returns the new integer value. + * @example + * + * _.parseInt('08'); + * // => 8 + */ + var parseInt = nativeParseInt(whitespace + '08') == 8 ? nativeParseInt : function(value, radix) { + // Firefox and Opera still follow the ES3 specified implementation of `parseInt` + return nativeParseInt(isString(value) ? value.replace(reLeadingSpacesAndZeros, '') : value, radix || 0); }; - } - /** - * Creates a new function that is restricted to one execution. Repeat calls to - * the function will return the value of the first call. - * - * @static - * @memberOf _ - * @category Functions - * @param {Function} func The function to restrict. - * @returns {Function} Returns the new restricted function. - * @example - * - * var initialize = _.once(createApplication); - * initialize(); - * initialize(); - * // Application is only created once. - */ - function once(func) { - var result, - ran = false; - - return function() { - if (ran) { - return result; + /** + * Produces a random number between `min` and `max` (inclusive). If only one + * argument is provided a number between `0` and the given number will be + * returned. If `floating` is truey or either `min` or `max` are floats a + * floating-point number will be returned instead of an integer. + * + * @static + * @memberOf _ + * @category Utilities + * @param {number} [min=0] The minimum possible value. + * @param {number} [max=1] The maximum possible value. + * @param {boolean} [floating=false] Specify returning a floating-point number. + * @returns {number} Returns a random number. + * @example + * + * _.random(0, 5); + * // => an integer between 0 and 5 + * + * _.random(5); + * // => also an integer between 0 and 5 + * + * _.random(5, true); + * // => a floating-point number between 0 and 5 + * + * _.random(1.2, 5.2); + * // => a floating-point number between 1.2 and 5.2 + */ + function random(min, max, floating) { + var noMin = min == null, + noMax = max == null; + + if (floating == null) { + if (typeof min == 'boolean' && noMax) { + floating = min; + min = 1; + } + else if (!noMax && typeof max == 'boolean') { + floating = max; + noMax = true; + } } - ran = true; - result = func.apply(this, arguments); - - // clear the `func` variable so the function may be garbage collected - func = null; - return result; - }; - } + if (noMin && noMax) { + max = 1; + } + min = +min || 0; + if (noMax) { + max = min; + min = 0; + } else { + max = +max || 0; + } + var rand = nativeRandom(); + return (floating || min % 1 || max % 1) + ? nativeMin(min + (rand * (max - min + parseFloat('1e-' + ((rand +'').length - 1)))), max) + : min + floor(rand * (max - min + 1)); + } - /** - * Creates a new function that, when called, invokes `func` with any additional - * `partial` arguments prepended to those passed to the new function. This method - * is similar `bind`, except it does **not** alter the `this` binding. - * - * @static - * @memberOf _ - * @category Functions - * @param {Function} func The function to partially apply arguments to. - * @param {Mixed} [arg1, arg2, ...] Arguments to be partially applied. - * @returns {Function} Returns the new partially applied function. - * @example - * - * var greet = function(greeting, name) { return greeting + ': ' + name; }; - * var hi = _.partial(greet, 'hi'); - * hi('moe'); - * // => 'hi: moe' - */ - function partial(func) { - var args = slice.call(arguments, 1), - argsLength = args.length; + /** + * Resolves the value of `property` on `object`. If `property` is a function + * it will be invoked with the `this` binding of `object` and its result returned, + * else the property value is returned. If `object` is falsey then `undefined` + * is returned. + * + * @static + * @memberOf _ + * @category Utilities + * @param {Object} object The object to inspect. + * @param {string} property The property to get the value of. + * @returns {*} Returns the resolved value. + * @example + * + * var object = { + * 'cheese': 'crumpets', + * 'stuff': function() { + * return 'nonsense'; + * } + * }; + * + * _.result(object, 'cheese'); + * // => 'crumpets' + * + * _.result(object, 'stuff'); + * // => 'nonsense' + */ + function result(object, property) { + if (object) { + var value = object[property]; + return isFunction(value) ? object[property]() : value; + } + } - return function() { - var result, - others = arguments; + /** + * A micro-templating method that handles arbitrary delimiters, preserves + * whitespace, and correctly escapes quotes within interpolated code. + * + * Note: In the development build, `_.template` utilizes sourceURLs for easier + * debugging. See http://www.html5rocks.com/en/tutorials/developertools/sourcemaps/#toc-sourceurl + * + * For more information on precompiling templates see: + * http://lodash.com/#custom-builds + * + * For more information on Chrome extension sandboxes see: + * http://developer.chrome.com/stable/extensions/sandboxingEval.html + * + * @static + * @memberOf _ + * @category Utilities + * @param {string} text The template text. + * @param {Object} data The data object used to populate the text. + * @param {Object} [options] The options object. + * @param {RegExp} [options.escape] The "escape" delimiter. + * @param {RegExp} [options.evaluate] The "evaluate" delimiter. + * @param {Object} [options.imports] An object to import into the template as local variables. + * @param {RegExp} [options.interpolate] The "interpolate" delimiter. + * @param {string} [sourceURL] The sourceURL of the template's compiled source. + * @param {string} [variable] The data object variable name. + * @returns {Function|string} Returns a compiled function when no `data` object + * is given, else it returns the interpolated text. + * @example + * + * // using the "interpolate" delimiter to create a compiled template + * var compiled = _.template('hello <%= name %>'); + * compiled({ 'name': 'moe' }); + * // => 'hello moe' + * + * // using the "escape" delimiter to escape HTML in data property values + * _.template('<%- value %>', { 'value': ' @@ -115,6 +156,7 @@

Mousemove Events:

Delayed Mousemove Events: delayed(fn, 200);

+

Sequenced Mousemove Events: sequenced(fn, 200);

Debounce Inmediate: _.debounce(fn, 200, true);

Debounce Inmediate: $.debounce(200, true, fn);

Debounce: _.debounce(fn, 200);

@@ -123,7 +165,7 @@

Throttle with trailing: _.throttle(fn, 200);

Throttle with trailing: $.throttle(200, false, fn);

Throttle: $.throttle(200, true, fn);

- + Fork me on GitHub diff --git a/main.js b/main.js index a48df24..8b9ed3a 100644 --- a/main.js +++ b/main.js @@ -9,6 +9,7 @@ $(document).ready(function(){ divThrottlejtrue = $('#throttlejtrue'), divThrottlejfalse = $('#throttlejfalse'), divDelayed = $('#delayedEvents'), + divSequenced = $('#sequencedEvents'), sidebar_mousemove = $('#sidebar-free'), counter = 0, next_color = 0, @@ -22,7 +23,8 @@ $(document).ready(function(){ lazyThrottle_true, lazyThrottlejtrue, lazyThrottlejfalse, - delayedUpdate; + delayedUpdate, + sequencedUpdate; function update(div, color){ @@ -45,6 +47,7 @@ $(document).ready(function(){ lazyThrottlejfalse = $.throttle(200, false, update); delayedUpdate = delayed(update, 200); + sequencedUpdate = sequenced(update, 200); } function updateEvents(){ @@ -57,6 +60,7 @@ $(document).ready(function(){ lazyThrottlejtrue(divThrottlejtrue, next_color); lazyThrottlejfalse(divThrottlejfalse, next_color); delayedUpdate(divDelayed, next_color); + sequencedUpdate(divSequenced, next_color); next_color++; if (next_color > 9){ next_color = 0; @@ -76,6 +80,7 @@ $(document).ready(function(){ divThrottlejtrue.html(''); divThrottlejfalse.html(''); divDelayed.html(''); + divSequenced.html(''); next_color = 0; counter = 0; clearInterval(drawing_automated); @@ -137,6 +142,7 @@ $(document).ready(function(){ divThrottlejfalse[0].appendChild(document.createElement('span')); divThrottle_true[0].appendChild(document.createElement('span')); divDelayed[0].appendChild(document.createElement('span')); + divSequenced[0].appendChild(document.createElement('span')); if (counter > 95){ clearInterval(drawing);