68d05b2a07
This just collapses all unit items from an iterator into one. This is
more useful when combined with higher-level abstractions, like
collecting to a `Result<(), E>` where you only care about errors:
```rust
use std::io::*;
data = vec![1, 2, 3, 4, 5];
let res: Result<()> = data.iter()
.map(|x| writeln!(stdout(), "{}", x))
.collect();
assert!(res.is_ok());
```
31 lines
1.1 KiB
Rust
31 lines
1.1 KiB
Rust
// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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use iter::FromIterator;
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/// Collapses all unit items from an iterator into one.
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///
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/// This is more useful when combined with higher-level abstractions, like
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/// collecting to a `Result<(), E>` where you only care about errors:
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///
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/// ```
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/// use std::io::*;
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/// let data = vec![1, 2, 3, 4, 5];
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/// let res: Result<()> = data.iter()
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/// .map(|x| writeln!(stdout(), "{}", x))
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/// .collect();
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/// assert!(res.is_ok());
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/// ```
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#[stable(feature = "unit_from_iter", since = "1.23.0")]
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impl FromIterator<()> for () {
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fn from_iter<I: IntoIterator<Item=()>>(iter: I) -> Self {
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iter.into_iter().for_each(|()| {})
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}
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}
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