src/test/run-pass/associated-const-use-impl-of-same-trait.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
  12 // The main purpose of this test is to ensure that different impls of the same
  13 // trait can refer to each other without setting off the static recursion check
  14 // (as long as there's no actual recursion).
  15
  16 trait Foo {
  17     const BAR: u32;
  18 }
  19
  20 struct IsFoo1;
  21
  22 impl Foo for IsFoo1 {
  23     const BAR: u32 = 1;
  24 }
  25
  26 struct IsFoo2;
  27
  28 impl Foo for IsFoo2 {
  29     const BAR: u32 = <IsFoo1 as Foo>::BAR;
  30 }
  31
  32 fn main() {
  33     assert_eq!(<IsFoo1>::BAR, <IsFoo2 as Foo>::BAR);
  34 }