src/test/compile-fail/vtable-res-trait-param.rs

   1 // Copyright 2012 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 trait TraitA {
  12     fn method_a(&self) -> isize;
  13 }
  14
  15 trait TraitB {
  16     fn gimme_an_a<A:TraitA>(&self, a: A) -> isize;
  17 }
  18
  19 impl TraitB for isize {
  20     fn gimme_an_a<A:TraitA>(&self, a: A) -> isize {
  21         a.method_a() + *self
  22     }
  23 }
  24
  25 fn call_it<B:TraitB>(b: B)  -> isize {
  26     let y = 4_usize;
  27     b.gimme_an_a(y) //~ ERROR the trait `TraitA` is not implemented
  28 }
  29
  30 fn main() {
  31     let x = 3;
  32     assert_eq!(call_it(x), 22);
  33 }