Returning from loops

One of the uses of a loop is to retry an operation until it succeeds. If the
operation returns a value though, you might need to pass it to the rest of the
code: put it after the break, and it will be returned by the loop
expression.

  1. fn main() {
  2.     let mut counter = 0;
  4.     let result = loop {
  5.         counter += 1;
  7.         if counter == 10 {
  8.             break counter * 2;
  9.         }
  10.     };
  12.     assert_eq!(result, 20);
  13. }