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Merged
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Feb 6, 2017
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Update if-let.md #38436

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6 changes: 4 additions & 2 deletions src/doc/book/if-let.md
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Original file line number Diff line number Diff line change
@@ -1,7 +1,8 @@
% if let

`if let` allows you to combine `if` and `let` together to reduce the overhead
of certain kinds of pattern matches.
`if let` allows us to match [patterns][patterns] within the condition of an [if][if].
As a consequence, we reduce the overhead of certain kinds of [pattern][patterns] matches
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After thinking about it more, I'm not a huge fan of the word "consequence" here since it usually describes the results of an action, and there's not really an action here. What about:

if let allows us to reduce...

or

This feature allows to reduce...

or

This allows us to reduce...

or something else. What do you think?

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What about this? I'd rather avoid using allow twice like that.

if let permits pattern matching within the condition of an if statement.
This allows us to reduce the overhead of certain kinds of [pattern][patterns] matches
and express them in a more convenient way.

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Sounds great :)

and express them in a more convenient way.

For example, let’s say we have some sort of `Option<T>`. We want to call a function
on it if it’s `Some<T>`, but do nothing if it’s `None`. That looks like this:
Expand Down Expand Up @@ -80,3 +81,4 @@ while let Some(x) = v.pop() {
```

[patterns]: patterns.html
[if]: if.html