introduction.md

Comparison Operators

Comparison operators compare two values and usually return a boolean (true or false). They are commonly used to make decisions in code.

PHP has identical comparisons and relational comparisons between numbers:

<?php

5 === 5; // => true
5 !== 0; // => true
3 < 7;   // => true
9 > 2;   // => true
5 <= 5;  // => true
4 >= 8;  // => false

Operator	Meaning
$a === $b	identical: equal and the same type
$a !== $b	not identical: different type or not equal
$a < $b	less than
$a > $b	greater than
$a <= $b	less than or equal to
$a >= $b	greater than or equal to

The spaceship operator

The spaceship operator (<=>) also compares two values, but it returns an integer instead of a boolean:

• -1 when the left value is less than the right value
• 0 when both values are equal
• 1 when the left value is greater than the right value

<?php

3 <=> 7; // => -1
5 <=> 5; // => 0
9 <=> 2; // => 1

Using comparisons in an if statement

A comparison can be used as the condition of an if statement. If the comparison is true, the code inside the braces runs:

<?php

if ($value === 10) {
    return 0.77;
}

if ($value >= 5) {
    return 0.9;
}