# array-lru

> A really fast LRU cache for array items (numeric keys)

Latest version **1.1.1** (published 2017-01-23) · MIT license · 0 weekly downloads

## Install

```sh
npm install array-lru
pnpm add array-lru
yarn add array-lru
bun add array-lru
```

## Health

**Score 15/100 (F)** — status: abandoned.

Positive: no vulnerabilities.

Warnings: low downloads; no types; no esm support.

Negative: abandoned; low maintenance score.

## Facts

| | |
|---|---|
| Version | 1.1.1 |
| Published | 2017-01-23 |
| First published | 2017-01-23 |
| Weekly downloads | 0 |
| License | MIT |
| TypeScript types | none |
| Module format | CommonJS |
| Dependencies | 0 |
| Known vulnerabilities | 0 |
| Install scripts | no |
| GitHub stars | 57 |
| Author | Mathias Buus |
| Maintainers | mafintosh |

## Links

- npm: https://www.npmjs.com/package/array-lru
- Repository: https://github.com/mafintosh/array-lru
- Issues: https://github.com/mafintosh/array-lru/issues
- npm.io page: https://npm.io/package/array-lru

## Recent versions

- 1.1.1 (latest) — 2017-01-23
- 1.1.0 — 2017-01-23
- 1.0.0 — 2017-01-23

## README

# arraylru

A really fast LRU cache for array items (numeric keys)

```
npm install array-lru
```

[![build status](https://travis-ci.org/mafintosh/array-lru.svg?branch=master)](http://travis-ci.org/mafintosh/array-lru)

Credit to [@dominictarr](https://github.com/dominictarr) for telling me about this neat algorithm for LRUs.

## Usage

``` js
var alru = require('array-lru')
var lru = alru(512) // create a lru that can contain 512 values

lru.set(42, {hello: 'world'})
console.log(lru.get(42)) // {hello: 'world'}
```

It works similar to a normal hash table except when a bucket is full it will
evict the oldest one from the bucket to make room for the new value.

## API

#### `var lru = alru(size, [options])`

Create a new LRU instance. Options include:

``` js
{
  collisions: 4, // how many hash collisions before evicting (default 4)
  evict: fn, // call this function with (index, value) when someone is evicted
  indexedValues: false // set to true if your values has a .index property
}
```

Size should be a multiple of `collections`. If not, it will be coerced into one.

### `var value = lru.get(index)`

Get a value from the cache. If the index is not found, `null` is returned.

### `lru.set(index, value)`

Insert a new value in the cache. If there is no room in the hash bucket that
`index` maps to, the oldest value in the bucket will be evicted.

### Performance

On my MacBook 12" I can set/get around 7.500.000 values per second, YMMV.
Run the benchmark using `npm run bench` to test it for yourself.

## License

MIT

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_Source: https://npm.io/package/array-lru · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._