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// run-pass
#![allow(non_camel_case_types)]
#![allow(dead_code)]
trait noisy {
fn speak(&mut self) -> isize;
}
struct dog {
barks: usize,
volume: isize,
}
impl dog {
fn bark(&mut self) -> isize {
println!("Woof {} {}", self.barks, self.volume);
self.barks += 1_usize;
if self.barks % 3_usize == 0_usize {
self.volume += 1;
}
if self.barks % 10_usize == 0_usize {
self.volume -= 2;
}
println!("Grrr {} {}", self.barks, self.volume);
self.volume
}
}
impl noisy for dog {
fn speak(&mut self) -> isize {
self.bark()
}
}
fn dog() -> dog {
dog {
volume: 0,
barks: 0_usize
}
}
#[derive(Clone)]
struct cat {
meows: usize,
how_hungry: isize,
name: String,
}
impl noisy for cat {
fn speak(&mut self) -> isize {
self.meow() as isize
}
}
impl cat {
pub fn meow_count(&self) -> usize {
self.meows
}
}
impl cat {
fn meow(&mut self) -> usize {
println!("Meow");
self.meows += 1_usize;
if self.meows % 5_usize == 0_usize {
self.how_hungry += 1;
}
self.meows
}
}
fn cat(in_x: usize, in_y: isize, in_name: String) -> cat {
cat {
meows: in_x,
how_hungry: in_y,
name: in_name
}
}
fn annoy_neighbors(critter: &mut dyn noisy) {
for _i in 0_usize..10 { critter.speak(); }
}
pub fn main() {
let mut nyan: cat = cat(0_usize, 2, "nyan".to_string());
let mut whitefang: dog = dog();
annoy_neighbors(&mut nyan);
annoy_neighbors(&mut whitefang);
assert_eq!(nyan.meow_count(), 10_usize);
assert_eq!(whitefang.volume, 1);
}
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