mirror of
https://github.com/rust-lang/rust
synced 2024-09-06 01:11:17 +00:00
35 lines
663 B
Rust
35 lines
663 B
Rust
//@ run-pass
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#![allow(unused_imports)]
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use std::thread;
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use std::sync::Mutex;
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fn par_for<I, F>(iter: I, f: F)
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where I: Iterator,
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I::Item: Send,
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F: Fn(I::Item) + Sync
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{
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for item in iter {
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f(item)
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}
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}
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fn sum(x: &[i32]) {
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let sum_lengths = Mutex::new(0);
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par_for(x.windows(4), |x| {
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*sum_lengths.lock().unwrap() += x.len()
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});
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assert_eq!(*sum_lengths.lock().unwrap(), (x.len() - 3) * 4);
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}
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fn main() {
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let mut elements = [0; 20];
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// iterators over references into this stack frame
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par_for(elements.iter_mut().enumerate(), |(i, x)| {
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*x = i as i32
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});
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sum(&elements)
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}
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