src/test/run-pass/specialization/specialization-basics.rs

   1 // Copyright 2014 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 #![feature(specialization)]
  12
  13 // Tests a variety of basic specialization scenarios and method
  14 // dispatch for them.
  15
  16 trait Foo {
  17     fn foo(&self) -> &'static str;
  18 }
  19
  20 impl<T> Foo for T {
  21     default fn foo(&self) -> &'static str {
  22         "generic"
  23     }
  24 }
  25
  26 impl<T: Clone> Foo for T {
  27     default fn foo(&self) -> &'static str {
  28         "generic Clone"
  29     }
  30 }
  31
  32 impl<T, U> Foo for (T, U) where T: Clone, U: Clone {
  33     default fn foo(&self) -> &'static str {
  34         "generic pair"
  35     }
  36 }
  37
  38 impl<T: Clone> Foo for (T, T) {
  39     default fn foo(&self) -> &'static str {
  40         "generic uniform pair"
  41     }
  42 }
  43
  44 impl Foo for (u8, u32) {
  45     default fn foo(&self) -> &'static str {
  46         "(u8, u32)"
  47     }
  48 }
  49
  50 impl Foo for (u8, u8) {
  51     default fn foo(&self) -> &'static str {
  52         "(u8, u8)"
  53     }
  54 }
  55
  56 impl<T: Clone> Foo for Vec<T> {
  57     default fn foo(&self) -> &'static str {
  58         "generic Vec"
  59     }
  60 }
  61
  62 impl Foo for Vec<i32> {
  63     fn foo(&self) -> &'static str {
  64         "Vec<i32>"
  65     }
  66 }
  67
  68 impl Foo for String {
  69     fn foo(&self) -> &'static str {
  70         "String"
  71     }
  72 }
  73
  74 impl Foo for i32 {
  75     fn foo(&self) -> &'static str {
  76         "i32"
  77     }
  78 }
  79
  80 struct NotClone;
  81
  82 trait MyMarker {}
  83 impl<T: Clone + MyMarker> Foo for T {
  84     default fn foo(&self) -> &'static str {
  85         "generic Clone + MyMarker"
  86     }
  87 }
  88
  89 #[derive(Clone)]
  90 struct MarkedAndClone;
  91 impl MyMarker for MarkedAndClone {}
  92
  93 fn  main() {
  94     assert!(NotClone.foo() == "generic");
  95     assert!(0u8.foo() == "generic Clone");
  96     assert!(vec![NotClone].foo() == "generic");
  97     assert!(vec![0u8].foo() == "generic Vec");
  98     assert!(vec![0i32].foo() == "Vec<i32>");
  99     assert!(0i32.foo() == "i32");
 100     assert!(String::new().foo() == "String");
 101     assert!(((), 0).foo() == "generic pair");
 102     assert!(((), ()).foo() == "generic uniform pair");
 103     assert!((0u8, 0u32).foo() == "(u8, u32)");
 104     assert!((0u8, 0u8).foo() == "(u8, u8)");
 105     assert!(MarkedAndClone.foo() == "generic Clone + MyMarker");
 106 }