src/test/run-pass/specialization/specialization-assoc-fns.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 // Test that non-method associated functions can be specialized
  12
  13 #![feature(specialization)]
  14
  15 trait Foo {
  16     fn mk() -> Self;
  17 }
  18
  19 impl<T: Default> Foo for T {
  20     default fn mk() -> T {
  21         T::default()
  22     }
  23 }
  24
  25 impl Foo for Vec<u8> {
  26     fn mk() -> Vec<u8> {
  27         vec![0]
  28     }
  29 }
  30
  31 fn main() {
  32     let v1: Vec<i32> = Foo::mk();
  33     let v2: Vec<u8> = Foo::mk();
  34
  35     assert!(v1.len() == 0);
  36     assert!(v2.len() == 1);
  37 }