rust/src/libcollections/deque.rs
2014-04-11 17:31:13 +08:00

125 lines
3.7 KiB
Rust

// Copyright 2013 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.
//! Container traits for collections
use std::container::Mutable;
/// A double-ended sequence that allows querying, insertion and deletion at both ends.
pub trait Deque<T> : Mutable {
/// Provide a reference to the front element, or None if the sequence is empty
fn front<'a>(&'a self) -> Option<&'a T>;
/// Provide a mutable reference to the front element, or None if the sequence is empty
fn front_mut<'a>(&'a mut self) -> Option<&'a mut T>;
/// Provide a reference to the back element, or None if the sequence is empty
fn back<'a>(&'a self) -> Option<&'a T>;
/// Provide a mutable reference to the back element, or None if the sequence is empty
fn back_mut<'a>(&'a mut self) -> Option<&'a mut T>;
/// Insert an element first in the sequence
fn push_front(&mut self, elt: T);
/// Insert an element last in the sequence
fn push_back(&mut self, elt: T);
/// Remove the last element and return it, or None if the sequence is empty
fn pop_back(&mut self) -> Option<T>;
/// Remove the first element and return it, or None if the sequence is empty
fn pop_front(&mut self) -> Option<T>;
}
#[cfg(test)]
pub mod bench {
extern crate test;
use self::test::Bencher;
use std::container::MutableMap;
use rand;
use rand::Rng;
pub fn insert_rand_n<M:MutableMap<uint,uint>>(n: uint,
map: &mut M,
b: &mut Bencher) {
// setup
let mut rng = rand::weak_rng();
map.clear();
for _ in range(0, n) {
map.insert(rng.gen::<uint>() % n, 1);
}
// measure
b.iter(|| {
let k = rng.gen::<uint>() % n;
map.insert(k, 1);
map.remove(&k);
})
}
pub fn insert_seq_n<M:MutableMap<uint,uint>>(n: uint,
map: &mut M,
b: &mut Bencher) {
// setup
map.clear();
for i in range(0u, n) {
map.insert(i*2, 1);
}
// measure
let mut i = 1;
b.iter(|| {
map.insert(i, 1);
map.remove(&i);
i = (i + 2) % n;
})
}
pub fn find_rand_n<M:MutableMap<uint,uint>>(n: uint,
map: &mut M,
b: &mut Bencher) {
// setup
let mut rng = rand::weak_rng();
let mut keys = Vec::from_fn(n, |_| rng.gen::<uint>() % n);
for k in keys.iter() {
map.insert(*k, 1);
}
rng.shuffle(keys.as_mut_slice());
// measure
let mut i = 0;
b.iter(|| {
map.find(keys.get(i));
i = (i + 1) % n;
})
}
pub fn find_seq_n<M:MutableMap<uint,uint>>(n: uint,
map: &mut M,
b: &mut Bencher) {
// setup
for i in range(0u, n) {
map.insert(i, 1);
}
// measure
let mut i = 0;
b.iter(|| {
let x = map.find(&i);
i = (i + 1) % n;
x
})
}
}