88 lines
2.6 KiB
Rust
88 lines
2.6 KiB
Rust
// Copyright 2015-2018 Parity Technologies (UK) Ltd.
|
|
// This file is part of Parity.
|
|
|
|
// Parity is free software: you can redistribute it and/or modify
|
|
// it under the terms of the GNU General Public License as published by
|
|
// the Free Software Foundation, either version 3 of the License, or
|
|
// (at your option) any later version.
|
|
|
|
// Parity is distributed in the hope that it will be useful,
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
// GNU General Public License for more details.
|
|
|
|
// You should have received a copy of the GNU General Public License
|
|
// along with Parity. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
//! This crate allows automatic caching of `T.len()` with an api that
|
|
//! allows drop in replacement for `parking_lot`
|
|
//! [`Mutex`](../lock_api/struct.Mutex.html)
|
|
//! and [`RwLock`](../lock_api/struct.RwLock.html) for most common use-cases.
|
|
//!
|
|
//! This crate implements `Len` for the following types:
|
|
//! `std::collections::{VecDeque, LinkedList, HashMap, BTreeMap, HashSet, BTreeSet, BinaryHeap}`
|
|
//!
|
|
//! ## Example
|
|
//!
|
|
//! ```rust
|
|
//! extern crate len_caching_lock;
|
|
//! use len_caching_lock::LenCachingMutex;
|
|
//!
|
|
//! fn main() {
|
|
//! let vec: Vec<i32> = Vec::new();
|
|
//! let len_caching_mutex = LenCachingMutex::new(vec);
|
|
//! assert_eq!(len_caching_mutex.lock().len(), len_caching_mutex.load_len());
|
|
//! len_caching_mutex.lock().push(0);
|
|
//! assert_eq!(1, len_caching_mutex.load_len());
|
|
//! }
|
|
//! ```
|
|
|
|
extern crate parking_lot;
|
|
use std::collections::{VecDeque, LinkedList, HashMap, BTreeMap, HashSet, BTreeSet, BinaryHeap};
|
|
use std::hash::Hash;
|
|
|
|
pub mod mutex;
|
|
pub mod rwlock;
|
|
|
|
pub use mutex::LenCachingMutex;
|
|
pub use rwlock::LenCachingRwLock;
|
|
|
|
/// Implement to allow a type with a len() method to be used
|
|
/// with [`LenCachingMutex`](mutex/struct.LenCachingMutex.html)
|
|
/// or [`LenCachingRwLock`](rwlock/struct.LenCachingRwLock.html)
|
|
pub trait Len {
|
|
fn len(&self) -> usize;
|
|
}
|
|
|
|
impl<T> Len for Vec<T> {
|
|
fn len(&self) -> usize { Vec::len(self) }
|
|
}
|
|
|
|
impl<T> Len for VecDeque<T> {
|
|
fn len(&self) -> usize { VecDeque::len(self) }
|
|
}
|
|
|
|
impl<T> Len for LinkedList<T> {
|
|
fn len(&self) -> usize { LinkedList::len(self) }
|
|
}
|
|
|
|
impl<K: Eq + Hash, V> Len for HashMap<K, V> {
|
|
fn len(&self) -> usize { HashMap::len(self) }
|
|
}
|
|
|
|
impl<K, V> Len for BTreeMap<K, V> {
|
|
fn len(&self) -> usize { BTreeMap::len(self) }
|
|
}
|
|
|
|
impl<T: Eq + Hash> Len for HashSet<T> {
|
|
fn len(&self) -> usize { HashSet::len(self) }
|
|
}
|
|
|
|
impl<T> Len for BTreeSet<T> {
|
|
fn len(&self) -> usize { BTreeSet::len(self) }
|
|
}
|
|
|
|
impl<T: Ord> Len for BinaryHeap<T> {
|
|
fn len(&self) -> usize { BinaryHeap::len(self) }
|
|
}
|