A WeakRef-based cache that automatically evicts entries when values are garbage collected

npm install weak-cache

import WeakCache from 'weak-cache';

const cache = new WeakCache({
	onEvict(key) {
		console.log(`${key} was garbage collected`);
	},
});

let value = {data: 'hello'};
cache.set('key', value);

console.log(cache.get('key'));
//=> {data: 'hello'}

console.log(cache.has('key'));
//=> true

Type: object

Type: (key) => void

Callback invoked with the key when an entry is evicted by garbage collection.

Returns the value for the key, or undefined if the key does not exist or its value has been garbage collected.

Set a key-value pair. The value must be an object (required for WeakRef). Throws TypeError for primitives.

Returns true if the key exists and the value is still alive.

Removes an entry. Returns true if the entry existed.

The approximate number of entries. May include entries whose values have been collected but not yet finalized.

• WeakRef - MDN WeakRef documentation
• FinalizationRegistry - MDN FinalizationRegistry documentation

MIT