src/test/run-pass/send-is-not-static-par-for.rs

   1 // Copyright 2015 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 // pretty-expanded FIXME #23616
  12
  13 #![feature(core, std_misc, scoped)]
  14 use std::thread;
  15 use std::sync::Mutex;
  16
  17 fn par_for<I, F>(iter: I, f: F)
  18     where I: Iterator,
  19           <I as Iterator>::Item: Send,
  20           F: Fn(<I as Iterator>::Item) + Sync
  21 {
  22     let f = &f;
  23     let _guards: Vec<_> = iter.map(|elem| {
  24         thread::scoped(move || {
  25             f(elem)
  26         })
  27     }).collect();
  28 }
  29
  30 fn sum(x: &[i32]) {
  31     let sum_lengths = Mutex::new(0);
  32     par_for(x.windows(4), |x| {
  33         *sum_lengths.lock().unwrap() += x.len()
  34     });
  35
  36     assert_eq!(*sum_lengths.lock().unwrap(), (x.len() - 3) * 4);
  37 }
  38
  39 fn main() {
  40     let mut elements = [0; 20];
  41
  42     // iterators over references into this stack frame
  43     par_for(elements.iter_mut().enumerate(), |(i, x)| {
  44         *x = i as i32
  45     });
  46
  47     sum(&elements)
  48 }