vendor/rustc-rayon/tests/run-pass/scope_join.rs

   1 extern crate rayon;
   2
   3 /// Test that one can emulate join with `scope`:
   4 fn pseudo_join<F, G>(f: F, g: G)
   5     where F: FnOnce() + Send,
   6           G: FnOnce() + Send,
   7 {
   8     rayon::scope(|s| {
   9         s.spawn(|_| g());
  10         f();
  11     });
  12 }
  13
  14 fn quick_sort<T:PartialOrd+Send>(v: &mut [T]) {
  15     if v.len() <= 1 {
  16         return;
  17     }
  18
  19     let mid = partition(v);
  20     let (lo, hi) = v.split_at_mut(mid);
  21     pseudo_join(|| quick_sort(lo), || quick_sort(hi));
  22 }
  23
  24 fn partition<T:PartialOrd+Send>(v: &mut [T]) -> usize {
  25     let pivot = v.len() - 1;
  26     let mut i = 0;
  27     for j in 0..pivot {
  28         if v[j] <= v[pivot] {
  29             v.swap(i, j);
  30             i += 1;
  31         }
  32     }
  33     v.swap(i, pivot);
  34     i
  35 }
  36
  37 pub fn is_sorted<T: Send + Ord>(v: &[T]) -> bool {
  38     (1..v.len()).all(|i| v[i-1] <= v[i])
  39 }
  40
  41 fn main() {
  42     let mut v: Vec<i32> = (0 .. 256).rev().collect();
  43     quick_sort(&mut v);
  44     assert!(is_sorted(&v));
  45 }