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loop_break_value book doc: remove some curiosities, regarding leodasvacas's comments

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Diggory Hardy 2017-05-09 19:34:00 +01:00
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commit 7488ff5c44
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src/doc/unstable-book/src/language-features/loop-break-value.md
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@ -10,19 +10,9 @@ Documentation to be appended to section G of the book.
### Loops as expressions
Like most things in Rust, loops are expressions; for example, the following is perfectly legal,
if rather useless:
```rust
let result = for n in 1..4 {
println!("Hello, {}", n);
};
assert_eq!(result, ());
```
Until now, all the loops you have seen evaluate to either `()` or `!`, the latter being special
syntax for "no value", meaning the loop never exits. A `loop` can instead evaluate to
a useful value via *break with value*:
Like most things in Rust, loops are expressions, and have a value; normally `()` unless the loop
never exits.
A `loop` can instead evaluate to a useful value via *break with value*:
```rust
// Find the first square number over 1000: