src/test/compile-fail/issue-23729.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 // Regression test for #23729
  12
  13 fn main() {
  14     let fib = {
  15         struct Recurrence {
  16             mem: [u64; 2],
  17             pos: usize,
  18         }
  19
  20         impl Iterator for Recurrence {
  21             //~^ ERROR E0046
  22             //~| NOTE missing `Item` in implementation
  23             #[inline]
  24             fn next(&mut self) -> Option<u64> {
  25                 if self.pos < 2 {
  26                     let next_val = self.mem[self.pos];
  27                     self.pos += 1;
  28                     Some(next_val)
  29                 } else {
  30                     let next_val = self.mem[0] + self.mem[1];
  31                     self.mem[0] = self.mem[1];
  32                     self.mem[1] = next_val;
  33                     Some(next_val)
  34                 }
  35             }
  36         }
  37
  38         Recurrence { mem: [0, 1], pos: 0 }
  39     };
  40
  41     for e in fib.take(10) {
  42         println!("{}", e)
  43     }
  44 }