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// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
// Test overloading of the `[]` operator. In particular test that it
// takes its argument *by reference*.
#![feature(core)]
use std::ops::Index;
struct AssociationList<K,V> {
pairs: Vec<AssociationPair<K,V>> }
#[derive(Clone)]
struct AssociationPair<K,V> {
key: K,
value: V
}
impl<K,V> AssociationList<K,V> {
fn push(&mut self, key: K, value: V) {
self.pairs.push(AssociationPair {key: key, value: value});
}
}
impl<'a, K: PartialEq + std::fmt::Debug, V:Clone> Index<&'a K> for AssociationList<K,V> {
type Output = V;
fn index(&self, index: &K) -> &V {
for pair in &self.pairs {
if pair.key == *index {
return &pair.value
}
}
panic!("No value found for key: {:?}", index);
}
}
pub fn main() {
let foo = "foo".to_string();
let bar = "bar".to_string();
let mut list = AssociationList {pairs: Vec::new()};
list.push(foo.clone(), 22);
list.push(bar.clone(), 44);
assert!(list[&foo] == 22);
assert!(list[&bar] == 44);
assert!(list[&foo] == 22);
assert!(list[&bar] == 44);
}
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