Rollup merge of #36929 - angelsl:issue-36683, r=steveklabnik

Reference: Mention `move` keyword for lambdas

From issue #36683
This commit is contained in:
Guillaume Gomez 2016-10-07 11:45:04 +02:00 committed by GitHub
commit bf41e9fee2

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@ -3110,10 +3110,12 @@ the lambda expression captures its environment by reference, effectively
borrowing pointers to all outer variables mentioned inside the function.
Alternately, the compiler may infer that a lambda expression should copy or
move values (depending on their type) from the environment into the lambda
expression's captured environment.
expression's captured environment. A lambda can be forced to capture its
environment by moving values by prefixing it with the `move` keyword.
In this example, we define a function `ten_times` that takes a higher-order
function argument, and we then call it with a lambda expression as an argument:
function argument, and we then call it with a lambda expression as an argument,
followed by a lambda expression that moves values from its environment.
```
fn ten_times<F>(f: F) where F: Fn(i32) {
@ -3123,6 +3125,9 @@ fn ten_times<F>(f: F) where F: Fn(i32) {
}
ten_times(|j| println!("hello, {}", j));
let word = "konnichiwa".to_owned();
ten_times(move |j| println!("{}, {}", word, j));
```
### Infinite loops