src/test/compile-fail/class-cast-to-trait.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 #![feature(box_syntax)]
  12
  13 trait noisy {
  14   fn speak(&self);
  15 }
  16
  17 struct cat {
  18   meows : usize,
  19
  20   how_hungry : isize,
  21   name : String,
  22 }
  23
  24 impl cat {
  25   pub fn eat(&self) -> bool {
  26     if self.how_hungry > 0 {
  27         println!("OM NOM NOM");
  28         self.how_hungry -= 2;
  29         return true;
  30     }
  31     else {
  32         println!("Not hungry!");
  33         return false;
  34     }
  35   }
  36 }
  37
  38 impl noisy for cat {
  39   fn speak(&self) { self.meow(); }
  40
  41 }
  42
  43 impl cat {
  44     fn meow(&self) {
  45       println!("Meow");
  46       self.meows += 1;
  47       if self.meows % 5 == 0 {
  48           self.how_hungry += 1;
  49       }
  50     }
  51 }
  52
  53 fn cat(in_x : usize, in_y : isize, in_name: String) -> cat {
  54     cat {
  55         meows: in_x,
  56         how_hungry: in_y,
  57         name: in_name
  58     }
  59 }
  60
  61 fn main() {
  62   let nyan: Box<noisy> = box cat(0, 2, "nyan".to_string()) as Box<noisy>;
  63   nyan.eat(); //~ ERROR no method named `eat` found
  64 }