src/test/ui/class-cast-to-trait.rs

   1 trait Noisy {
   2   fn speak(&self);
   3 }
   4
   5 struct Cat {
   6   meows : usize,
   7
   8   how_hungry : isize,
   9   name : String,
  10 }
  11
  12 impl Cat {
  13   pub fn eat(&self) -> bool {
  14     if self.how_hungry > 0 {
  15         println!("OM NOM NOM");
  16         self.how_hungry -= 2;
  17         return true;
  18     }
  19     else {
  20         println!("Not hungry!");
  21         return false;
  22     }
  23   }
  24 }
  25
  26 impl Noisy for Cat {
  27   fn speak(&self) { self.meow(); }
  28
  29 }
  30
  31 impl Cat {
  32     fn meow(&self) {
  33       println!("Meow");
  34       self.meows += 1;
  35       if self.meows % 5 == 0 {
  36           self.how_hungry += 1;
  37       }
  38     }
  39 }
  40
  41 fn cat(in_x : usize, in_y : isize, in_name: String) -> Cat {
  42     Cat {
  43         meows: in_x,
  44         how_hungry: in_y,
  45         name: in_name
  46     }
  47 }
  48
  49
  50
  51 fn main() {
  52   let nyan: Box<dyn Noisy> = Box::new(cat(0, 2, "nyan".to_string())) as Box<dyn Noisy>;
  53   nyan.eat(); //~ ERROR no method named `eat` found
  54 }