weakmap-polyfill

weakmap-polyfill
================


ECMAScript6 WeakMap polyfill.

Installation

$3

``bash
$ npm install --save weakmap-polyfill
`

$3

Import or require weakmap-polyfill, then WeakMap will be defined in the global scope if native WeakMap is not supported in running environment.

#### using import

`javascript
import 'weakmap-polyfill';
const weakMap = new WeakMap();
`

#### using require

`javascript
require('weakmap-polyfill');
var weakMap = new WeakMap();
`

#### browser (standalone)

`html


`

Compatibility

* Chrome 15
* Firefox 3
* IE 7
* Safari 4
* Opera 11.5
* Edge

$3

* Browser Test
* Browser Test for Legacy

Limitations

This polyfill has following few limitations.

* WeakMap iterable` argument is not supported. ([23.3.1.1 WeakMap ( \[ iterable \] )](https://www.ecma-international.org/ecma-262/6.0/index.html#sec-weakmap-iterable))
* Frozen and sealed objects are not supported.
* The values held by a WeakMap can't be collected once the map itself is GCed, since the values here are tied to the keys. #4

License

MIT