Roughly inspired by Mark Miller's and Kris Kowal's WeakMap implementation.
Differences are:
- Assumes compliant ES5 environment (no weird ES3 workarounds or hacks)
- Well modularized CJS style
- Based on one solution.
- Will fail on non extensible objects provided as keys
$ npm install es6-weak-map
To port it to Browser or any other (non CJS) environment, use your favorite CJS bundler. No favorite yet? Try: Browserify, Webmake or Webpack
If you want to make sure your environment implements WeakMap
, do:
require("es6-weak-map/implement");
If you'd like to use native version when it exists and fallback to polyfill if it doesn't, but without implementing WeakMap
on global scope, do:
var WeakMap = require("es6-weak-map");
If you strictly want to use polyfill even if native WeakMap
exists, do:
var WeakMap = require("es6-weak-map/polyfill");
Best is to refer to specification. Still if you want quick look, follow example:
var WeakMap = require("es6-weak-map");
var map = new WeakMap();
var obj = {};
map.set(obj, "foo"); // map
map.get(obj); // 'foo'
map.has(obj); // true
map.delete(obj); // true
map.get(obj); // undefined
map.has(obj); // false
map.set(obj, "bar"); // map
map.has(obj); // false
$ npm test
To report a security vulnerability, please use the Tidelift security contact. Tidelift will coordinate the fix and disclosure.
Tidelift helps make open source sustainable for maintainers while giving companies
assurances about security, maintenance, and licensing for their dependencies.