Tiny & Fast LRU Implementation as possible.

Features

Fast: High performance (See benchmark).
Simple: The whole project is ~60 lines of code.
Lightweight: The package weighs less than a megabyte, with zero dependencies.

There are a lot of LRU implementations, but most of them have a poor perfomance and they are hard to understand.

hyperlru is an Abstract LRU implementation using traditional and efficienty data structures:

Double Linked List: It maintains the least recent list of items.
Hash Table It keeps the data for easily access to cache content.

For use it, you need to provide one of the created providers:

Install

$ npm install hyperlru --save

Usage

const hyperlru = require('hyperlru')
const myProvider = require('my-hyperlru-provider')

const createLRU = hyperlru(myProvider)
const cache = createLRU({max: 1000})

Benchmark

name	size	gzip	set	get1	update	get2	evict
lru-fast	2.34 kB	793 B	6855	27105	21550	25159	4003
tiny-lru	4 kB	1.64 kB	4159	10746	18909	15925	4042
lru_cache	2.19 kB	756 B	5320	14489	10785	15963	4242
simple-lru-cache	1.43 kB	565 B	3289	12134	8600	15266	3334
hyperlru-object	433 B	265 B	1152	8800	6205	8635	1039
hashlru	628 B	332 B	4438	5834	4703	5960	3474
hyperlru-map	329 B	232 B	850	4555	4030	4397	690
lru	6.07 kB	1.86 kB	2672	3302	3142	3898	1347
lru-cache	19.1 kB	6.23 kB	989	4702	3034	4536	773
secondary-cache	22.6 kB	6.54 kB	1427	2292	2740	4579	1164
quick-lru	1.23 kB	489 B	2441	2075	2525	2119	2525
modern-lru	2.27 kB	907 B	1019	2531	2021	2456	731
mkc	10.5 kB	3.61 kB	729	1230	715	1129	575

API

hyperlru([options])

options

max

Type: number
Default: 1000

Max of element to keep into the cache.

.set(key, value)

Set the value of the key and mark the key as most recently used.

It returns the value.

.get(key)

Query the value of the key and mark the key as most recently used.

It returns the value of key if found; undefined otherwise.

.peek(key)

Query the value of the key without marking the key as most recently used.

It returns the value of key if found; undefined otherwise.

.keys()

It retrieves all the keys currently in the cache.

.values()

It retrieves all the values currently in the cache.

.clear()

Clear all the elements in the cache.

.remove(key)

Remove the value from the cache.

Returns: value of key if found; undefined otherwise.