nanolru

library1.0.0jsnpmunverified

A simple O(1) LRU cache for Node.js, version 1.0.0 (stable). Forked from 'lru' to remove the dependency on 'events', providing a minimal, zero-dependency implementation. Supports set, get, peek, remove, and clear operations with configurable max size and optional max age for automatic eviction. Suitable for scenarios requiring a lightweight, fast LRU cache without external dependencies.

storage

npm install nanolru

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INSTALL

IMPORT

SIG · NANOLRU

nanolru

storagejavascriptv1.0.0

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

LRU

✓ const LRU = require('nanolru')

✗ import LRU from 'nanolru'

CommonJS module. No ES module export, so import syntax does not work.

LRU

✓ const LRU = require('nanolru')

✗ var LRU = require('nanolru').LRU

Default export is the constructor; no named export.

LRU (as factory)

✓ const cache = new LRU(100)

✗ const cache = new LRU({ max: 100 })

Constructor accepts max length as a number, or an options object with 'max' and 'maxAge'.

Creates an LRU cache with max size 2, demonstrates set/get, eviction, remove, keys, and clear.

const LRU = require('nanolru'); const cache = new LRU(2); cache.set('foo', 'bar'); console.log(cache.get('foo')); // => 'bar' cache.set('foo2', 'bar2'); cache.set('foo3', 'bar3'); // evicts 'foo' console.log(cache.get('foo3')); // => 'bar3' console.log(cache.length); // => 1 cache.remove('foo2'); console.log(cache.keys); // => ['foo3'] cache.clear(); console.log(cache.length); // => 0

Debug

Known issues

gotchaThe constructor expects the first argument as max length (number) or options object. Passing a single number works; passing string or undefined may cause unexpected behavior.

fix

Always pass a number or { max: number, maxAge?: number } to the constructor.

affects: >=1.0.0

gotchaThe 'keys' property returns an array of keys, but it is not documented as read-only; mutating it might affect internal state.

fix

Treat 'cache.keys' as read-only. Do not push, splice, or reassign.

affects: >=1.0.0

gotchaPeek method does not update the recentness of the key, but it still returns the value if present. Ensure you intend to not mark the key as recently used.

fix

Use cache.get(key) to mark as recently used, or cache.peek(key) to check without updating order.

affects: >=1.0.0

Errors

Common errors & fixes

TypeError: LRU is not a constructor

Using ES import syntax (import LRU from 'nanolru') which does not work in CommonJS module.

fix

Use const LRU = require('nanolru')

TypeError: cache.set is not a function

Cache instance created incorrectly, e.g., calling LRU() without new or passing invalid options.

fix

Ensure you use new LRU(max) or new LRU({ max: max })

Upgrade

Version history

1.0.0latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

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Resources

githubhttps://github.com/s3ththompson/nanolru ↗

packagenanolru ↗

homepagehttp://github.com/s3ththompson/nanolru ↗