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trait Noisy {
fn speak(&mut self);
}
struct Cat {
meows : usize,
how_hungry : isize,
name : String,
}
impl Cat {
pub fn eat(&mut self) -> bool {
if self.how_hungry > 0 {
println!("OM NOM NOM");
self.how_hungry -= 2;
return true;
}
else {
println!("Not hungry!");
return false;
}
}
}
impl Noisy for Cat {
fn speak(&mut self) { self.meow(); }
}
impl Cat {
fn meow(&mut self) {
println!("Meow");
self.meows += 1;
if self.meows % 5 == 0 {
self.how_hungry += 1;
}
}
}
fn cat(in_x : usize, in_y : isize, in_name: String) -> Cat {
Cat {
meows: in_x,
how_hungry: in_y,
name: in_name
}
}
fn main() {
let nyan: Box<dyn Noisy> = Box::new(cat(0, 2, "nyan".to_string())) as Box<dyn Noisy>;
nyan.eat(); //~ ERROR no method named `eat` found
}
|
