src/test/run-pass/class-implement-traits.rs

   1 // Copyright 2012-2014 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
  12 trait noisy {
  13     fn speak(&mut self);
  14 }
  15
  16 #[derive(Clone)]
  17 struct cat {
  18     meows : uint,
  19
  20     how_hungry : int,
  21     name : String,
  22 }
  23
  24 impl cat {
  25     fn meow(&mut self) {
  26         println!("Meow");
  27         self.meows += 1u;
  28         if self.meows % 5u == 0u {
  29             self.how_hungry += 1;
  30         }
  31     }
  32 }
  33
  34 impl cat {
  35     pub fn eat(&mut self) -> bool {
  36         if self.how_hungry > 0 {
  37             println!("OM NOM NOM");
  38             self.how_hungry -= 2;
  39             return true;
  40         } else {
  41             println!("Not hungry!");
  42             return false;
  43         }
  44     }
  45 }
  46
  47 impl noisy for cat {
  48     fn speak(&mut self) { self.meow(); }
  49 }
  50
  51 fn cat(in_x : uint, in_y : int, in_name: String) -> cat {
  52     cat {
  53         meows: in_x,
  54         how_hungry: in_y,
  55         name: in_name.clone()
  56     }
  57 }
  58
  59
  60 fn make_speak<C:noisy>(mut c: C) {
  61     c.speak();
  62 }
  63
  64 pub fn main() {
  65     let mut nyan = cat(0u, 2, "nyan".to_string());
  66     nyan.eat();
  67     assert!((!nyan.eat()));
  68     for _ in range(1u, 10u) {
  69         make_speak(nyan.clone());
  70     }
  71 }