es6-map-shim

A polyfill ES6 Map that closely follows the latest spec

Usage no npm install needed!

<script type="module">
  import es6MapShim from 'https://cdn.skypack.dev/es6-map-shim';
</script>

README

es6-map-shim - A polyfill for ES6 Maps

This is a destructive shim that implements the ES6 Map specification as closely as possible.

var map = new Map([['foo', 'bar'], [-0, function(){}]]);
map.set(null, 42);

map.get(-0);
=> function(){}

map.has(null);
=> true

map.keys();
=> ['foo', -0, null]

map.values();
=> ['bar', function(){}, 42]

map.items();
=> [['foo', 'bar'], [-0, function(){}], [null, 42]]

map.forEach(function(value, key, mapReference) {
  console.log(typeof value);
});
=> 'string'\n'function'\n'number'\n

var iterator = map.iterator();
iterator.next();
=> ['foo', 'bar']
iterator.next();
=> [-0, function(){}]

map.delete(null);
=> true

// Remove all items
map.clear();
map.size;
=> 0

map.toString();
=> '[object Map]'

Installation

In browsers, include es6-map-shim.js in your page:

<script type="text/javascript" src="https://raw.github.com/eriwen/es6-map-shim/master/es6-map-shim.js"></script>

You can install this via:

  • npm for node.js v0.8+: npm install es6-map-shim
  • component(1): component install eriwen/es6-map-shim
  • bower: bower install es6-map-shim

Environment Support

If you also use the es5-shim, you can use this in:

  • IE7+ (not fully tested yet)
  • Firefox 15+
  • Google Chrome 21+
  • Safari 4+
  • Opera 12+
  • Node.js 0.8+
  • PhantomJS