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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*.
use std::ops::Index;
struct AssociationList<K,V> {
pairs: ~[AssociationPair<K,V>]
}
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<K:Eq,V:Copy> Index<K,V> for AssociationList<K,V> {
fn index(&self, index: &K) -> V {
for self.pairs.iter().advance |pair| {
if pair.key == *index {
return copy pair.value;
}
}
fail!("No value found for key: %?", index);
}
}
pub fn main() {
let foo = ~"foo";
let bar = ~"bar";
let mut list = AssociationList {pairs: ~[]};
list.push(copy foo, 22);
list.push(copy bar, 44);
assert!(list[foo] == 22)
assert!(list[bar] == 44)
assert!(list[foo] == 22)
assert!(list[bar] == 44)
}
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