src/test/ui/for-loop-while/while-let.rs

   1 // run-pass
   2
   3 use std::collections::BinaryHeap;
   4
   5 fn make_pq() -> BinaryHeap<isize> {
   6     BinaryHeap::from(vec![1,2,3])
   7 }
   8
   9 pub fn main() {
  10     let mut pq = make_pq();
  11     let mut sum = 0;
  12     while let Some(x) = pq.pop() {
  13         sum += x;
  14     }
  15     assert_eq!(sum, 6);
  16
  17     pq = make_pq();
  18     sum = 0;
  19     'a: while let Some(x) = pq.pop() {
  20         sum += x;
  21         if x == 2 {
  22             break 'a;
  23         }
  24     }
  25     assert_eq!(sum, 5);
  26
  27     pq = make_pq();
  28     sum = 0;
  29     'a2: while let Some(x) = pq.pop() {
  30         if x == 3 {
  31             continue 'a2;
  32         }
  33         sum += x;
  34     }
  35     assert_eq!(sum, 3);
  36
  37     let mut pq1 = make_pq();
  38     sum = 0;
  39     while let Some(x) = pq1.pop() {
  40         let mut pq2 = make_pq();
  41         while let Some(y) = pq2.pop() {
  42             sum += x * y;
  43         }
  44     }
  45     assert_eq!(sum, 6 + 12 + 18);
  46 }