azu / map-like

ES2015 Map like object. Tiny `Map` shim.

map-like

ECMAScript Map like class.

It has same API with Map - JavaScript | MDN.

This library is tiny - 1.5kB(gzip).

✈ bundle-size map-like
[email protected]

env  bundle   minify   gzip
--   5.73 kB  3.08 kB  1.5 kB

Limitation ⚠️

• Not support Symbol.Iterator
  • This means that MapLike object is not iterable.
• Return Array insteadof Iterator object.
  • MapLike#values(), MapLike#keys(), MapLike#entries() return a Array.
• Not support toString()

Why Map-like?

I've created Map-like to avoid Symbol.iterator. Because, the transpiled code of Iterator has a run-time cost at the current moment.

• Faster Collection Iterators | Benedikt Meurer

So, MapLike does not support Iterator object.

Install

Install with npm:

npm install map-like

Usage

const { MapLike } = require("map-like");
const map = new MapLike(["key", "value"]);
const value = map.get("key");
map.set("newKey", "newValue");

API

MapLike

ES6 Map like object. See Map - JavaScript | MDN

size

return map size

Returns: Number

entries(): Array

entries [[key, value], [key, value]] value

Returns: Array

keys(): Array

get keys

Returns: Array

values(): Array

get values

Returns: Array

get(key: Any): Any

Parameters

• key: Any - The key of the element to return from the Map object.

Returns: Any

has(key: Any): boolean

has value of key

Parameters

• key: Any - The key of the element to return from the Map object.

Returns: boolean

set(key: Any, value: Any): MapLike

set value for key

Parameters

• key: Any - The key of the element to return from the Map object.
• value: Any

Returns: MapLike

delete(key: Any): boolean

delete value for key

Parameters

• key: Any - The key of the element to return from the Map object.

Returns: boolean

clear(): MapLike

clear defined key,value

Returns: MapLike

forEach(handler: function (value, key, map), thisArg: [Any])

forEach map

Parameters

• handler: function (value, key, map)
• thisArg: [Any]

Changelog

See Releases page.

Running tests

Install devDependencies and Run npm test:

npm i -d && npm test

Contributing

Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.

1. Fork it!
2. Create your feature branch: git checkout -b my-new-feature
3. Commit your changes: git commit -am 'Add some feature'
4. Push to the branch: git push origin my-new-feature
5. Submit a pull request :D

Author

• github/azu
• twitter/azu_re

License

MIT © azu

Thanks

Test MapLike with test-case of https://github.com/Financial-Times/polyfill-service/blob/master/polyfills/Map/tests.js.

map-like's Issues

add d.ts

From almin/almin#68