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// run-pass
#![allow(dead_code)]
#![allow(non_camel_case_types)]
use std::cmp;
#[derive(Copy, Clone, Debug)]
enum cat_type { tuxedo, tabby, tortoiseshell }
impl cmp::PartialEq for cat_type {
fn eq(&self, other: &cat_type) -> bool {
((*self) as usize) == ((*other) as usize)
}
fn ne(&self, other: &cat_type) -> bool { !(*self).eq(other) }
}
// Very silly -- this just returns the value of the name field
// for any isize value that's less than the meows field
// ok: T should be in scope when resolving the trait ref for map
struct cat<T> {
// Yes, you can have negative meows
meows : isize,
how_hungry : isize,
name : T,
}
impl<T> cat<T> {
pub fn speak(&mut self) { self.meow(); }
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;
}
}
fn len(&self) -> usize { self.meows as usize }
fn is_empty(&self) -> bool { self.meows == 0 }
fn clear(&mut self) {}
fn contains_key(&self, k: &isize) -> bool { *k <= self.meows }
fn find(&self, k: &isize) -> Option<&T> {
if *k <= self.meows {
Some(&self.name)
} else {
None
}
}
fn insert(&mut self, k: isize, _: T) -> bool {
self.meows += k;
true
}
fn find_mut(&mut self, _k: &isize) -> Option<&mut T> { panic!() }
fn remove(&mut self, k: &isize) -> bool {
if self.find(k).is_some() {
self.meows -= *k; true
} else {
false
}
}
fn pop(&mut self, _k: &isize) -> Option<T> { panic!() }
fn swap(&mut self, _k: isize, _v: T) -> Option<T> { panic!() }
}
impl<T> cat<T> {
pub fn get(&self, k: &isize) -> &T {
match self.find(k) {
Some(v) => { v }
None => { panic!("epic fail"); }
}
}
pub fn new(in_x: isize, in_y: isize, in_name: T) -> cat<T> {
cat{meows: in_x, how_hungry: in_y, name: in_name }
}
}
impl<T> cat<T> {
fn meow(&mut self) {
self.meows += 1;
println!("Meow {}", self.meows);
if self.meows % 5 == 0 {
self.how_hungry += 1;
}
}
}
pub fn main() {
let mut nyan: cat<String> = cat::new(0, 2, "nyan".to_string());
for _ in 1_usize..5 { nyan.speak(); }
assert_eq!(*nyan.find(&1).unwrap(), "nyan".to_string());
assert_eq!(nyan.find(&10), None);
let mut spotty: cat<cat_type> = cat::new(2, 57, cat_type::tuxedo);
for _ in 0_usize..6 { spotty.speak(); }
assert_eq!(spotty.len(), 8);
assert!((spotty.contains_key(&2)));
assert_eq!(spotty.get(&3), &cat_type::tuxedo);
}
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