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diff --git a/node_modules/core-js/README.md b/node_modules/core-js/README.md deleted file mode 100644 index 7cfbe89d5..000000000 --- a/node_modules/core-js/README.md +++ /dev/null @@ -1,2289 +0,0 @@ -# core-js - -[](https://gitter.im/zloirock/core-js?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge) [](https://www.npmjs.com/package/core-js) [](http://npm-stat.com/charts.html?package=core-js&author=&from=2014-11-18) [](https://travis-ci.org/zloirock/core-js) [](https://david-dm.org/zloirock/core-js?type=dev) -#### As advertising: the author is looking for a good job :) - -Modular standard library for JavaScript. Includes polyfills for [ECMAScript 5](#ecmascript-5), [ECMAScript 6](#ecmascript-6): [promises](#ecmascript-6-promise), [symbols](#ecmascript-6-symbol), [collections](#ecmascript-6-collections), iterators, [typed arrays](#ecmascript-6-typed-arrays), [ECMAScript 7+ proposals](#ecmascript-7-proposals), [setImmediate](#setimmediate), etc. Some additional features such as [dictionaries](#dict) or [extended partial application](#partial-application). You can require only needed features or use it without global namespace pollution. - -[*Example*](http://goo.gl/a2xexl): -```js -Array.from(new Set([1, 2, 3, 2, 1])); // => [1, 2, 3] -'*'.repeat(10); // => '**********' -Promise.resolve(32).then(x => console.log(x)); // => 32 -setImmediate(x => console.log(x), 42); // => 42 -``` - -[*Without global namespace pollution*](http://goo.gl/paOHb0): -```js -var core = require('core-js/library'); // With a modular system, otherwise use global `core` -core.Array.from(new core.Set([1, 2, 3, 2, 1])); // => [1, 2, 3] -core.String.repeat('*', 10); // => '**********' -core.Promise.resolve(32).then(x => console.log(x)); // => 32 -core.setImmediate(x => console.log(x), 42); // => 42 -``` - -### Index -- [Usage](#usage) - - [Basic](#basic) - - [CommonJS](#commonjs) - - [Custom build](#custom-build-from-the-command-line) -- [Supported engines](#supported-engines) -- [Features](#features) - - [ECMAScript 5](#ecmascript-5) - - [ECMAScript 6](#ecmascript-6) - - [ECMAScript 6: Object](#ecmascript-6-object) - - [ECMAScript 6: Function](#ecmascript-6-function) - - [ECMAScript 6: Array](#ecmascript-6-array) - - [ECMAScript 6: String](#ecmascript-6-string) - - [ECMAScript 6: RegExp](#ecmascript-6-regexp) - - [ECMAScript 6: Number](#ecmascript-6-number) - - [ECMAScript 6: Math](#ecmascript-6-math) - - [ECMAScript 6: Date](#ecmascript-6-date) - - [ECMAScript 6: Promise](#ecmascript-6-promise) - - [ECMAScript 6: Symbol](#ecmascript-6-symbol) - - [ECMAScript 6: Collections](#ecmascript-6-collections) - - [ECMAScript 6: Typed Arrays](#ecmascript-6-typed-arrays) - - [ECMAScript 6: Reflect](#ecmascript-6-reflect) - - [ECMAScript 7+ proposals](#ecmascript-7-proposals) - - [stage 4 proposals](#stage-4-proposals) - - [stage 3 proposals](#stage-3-proposals) - - [stage 2 proposals](#stage-2-proposals) - - [stage 1 proposals](#stage-1-proposals) - - [stage 0 proposals](#stage-0-proposals) - - [pre-stage 0 proposals](#pre-stage-0-proposals) - - [Web standards](#web-standards) - - [setTimeout / setInterval](#settimeout--setinterval) - - [setImmediate](#setimmediate) - - [iterable DOM collections](#iterable-dom-collections) - - [Non-standard](#non-standard) - - [Object](#object) - - [Dict](#dict) - - [partial application](#partial-application) - - [Number Iterator](#number-iterator) - - [escaping strings](#escaping-strings) - - [delay](#delay) - - [helpers for iterators](#helpers-for-iterators) -- [Missing polyfills](#missing-polyfills) -- [Changelog](./CHANGELOG.md) - -## Usage -### Basic -``` -npm i core-js -bower install core.js -``` - -```js -// Default -require('core-js'); -// Without global namespace pollution -var core = require('core-js/library'); -// Shim only -require('core-js/shim'); -``` -If you need complete build for browser, use builds from `core-js/client` path: - -* [default](https://raw.githack.com/zloirock/core-js/v2.5.7/client/core.min.js): Includes all features, standard and non-standard. -* [as a library](https://raw.githack.com/zloirock/core-js/v2.5.7/client/library.min.js): Like "default", but does not pollute the global namespace (see [2nd example at the top](#core-js)). -* [shim only](https://raw.githack.com/zloirock/core-js/v2.5.7/client/shim.min.js): Only includes the standard methods. - -Warning: if you use `core-js` with the extension of native objects, require all needed `core-js` modules at the beginning of entry point of your application, otherwise, conflicts may occur. - -### CommonJS -You can require only needed modules. - -```js -require('core-js/fn/set'); -require('core-js/fn/array/from'); -require('core-js/fn/array/find-index'); -Array.from(new Set([1, 2, 3, 2, 1])); // => [1, 2, 3] -[1, 2, NaN, 3, 4].findIndex(isNaN); // => 2 - -// or, w/o global namespace pollution: - -var Set = require('core-js/library/fn/set'); -var from = require('core-js/library/fn/array/from'); -var findIndex = require('core-js/library/fn/array/find-index'); -from(new Set([1, 2, 3, 2, 1])); // => [1, 2, 3] -findIndex([1, 2, NaN, 3, 4], isNaN); // => 2 -``` -Available entry points for methods / constructors, as above examples, and namespaces: for example, `core-js/es6/array` (`core-js/library/es6/array`) contains all [ES6 `Array` features](#ecmascript-6-array), `core-js/es6` (`core-js/library/es6`) contains all ES6 features. - -##### Caveats when using CommonJS API: - -* `modules` path is internal API, does not inject all required dependencies and can be changed in minor or patch releases. Use it only for a custom build and / or if you know what are you doing. -* `core-js` is extremely modular and uses a lot of very tiny modules, because of that for usage in browsers bundle up `core-js` instead of usage loader for each file, otherwise, you will have hundreds of requests. - -#### CommonJS and prototype methods without global namespace pollution -In the `library` version, we can't pollute prototypes of native constructors. Because of that, prototype methods transformed to static methods like in examples above. `babel` `runtime` transformer also can't transform them. But with transpilers we can use one more trick - [bind operator and virtual methods](https://github.com/zenparsing/es-function-bind). Special for that, available `/virtual/` entry points. Example: -```js -import fill from 'core-js/library/fn/array/virtual/fill'; -import findIndex from 'core-js/library/fn/array/virtual/find-index'; - -Array(10)::fill(0).map((a, b) => b * b)::findIndex(it => it && !(it % 8)); // => 4 - -// or - -import {fill, findIndex} from 'core-js/library/fn/array/virtual'; - -Array(10)::fill(0).map((a, b) => b * b)::findIndex(it => it && !(it % 8)); // => 4 - -``` - -### Custom build (from the command-line) -``` -npm i core-js && cd node_modules/core-js && npm i -npm run grunt build:core.dict,es6 -- --blacklist=es6.promise,es6.math --library=on --path=custom uglify -``` -Where `core.dict` and `es6` are modules (namespaces) names, which will be added to the build, `es6.promise` and `es6.math` are modules (namespaces) names, which will be excluded from the build, `--library=on` is flag for build without global namespace pollution and `custom` is target file name. - -Available namespaces: for example, `es6.array` contains [ES6 `Array` features](#ecmascript-6-array), `es6` contains all modules whose names start with `es6`. - -### Custom build (from external scripts) - -[`core-js-builder`](https://www.npmjs.com/package/core-js-builder) package exports a function that takes the same parameters as the `build` target from the previous section. This will conditionally include or exclude certain parts of `core-js`: - -```js -require('core-js-builder')({ - modules: ['es6', 'core.dict'], // modules / namespaces - blacklist: ['es6.reflect'], // blacklist of modules / namespaces, by default - empty list - library: false, // flag for build without global namespace pollution, by default - false - umd: true // use UMD wrapper for export `core` object, by default - true -}).then(code => { - // ... -}).catch(error => { - // ... -}); -``` -## Supported engines -**Tested in:** -- Chrome 26+ -- Firefox 4+ -- Safari 5+ -- Opera 12+ -- Internet Explorer 6+ (sure, IE8- with ES3 limitations) -- Edge -- Android Browser 2.3+ -- iOS Safari 5.1+ -- PhantomJS 1.9 / 2.1 -- NodeJS 0.8+ - -...and it doesn't mean `core-js` will not work in other engines, they just have not been tested. - -## Features: -[*CommonJS entry points:*](#commonjs) -``` -core-js(/library) <- all features -core-js(/library)/shim <- only polyfills -``` -### ECMAScript 5 -All features moved to the [`es6` namespace](#ecmascript-6), here just a list of features: -```js -Object - .create(proto | null, descriptors?) -> object - .getPrototypeOf(object) -> proto | null - .defineProperty(target, key, desc) -> target, cap for ie8- - .defineProperties(target, descriptors) -> target, cap for ie8- - .getOwnPropertyDescriptor(object, key) -> desc - .getOwnPropertyNames(object) -> array - .keys(object) -> array - .seal(object) -> object, cap for ie8- - .freeze(object) -> object, cap for ie8- - .preventExtensions(object) -> object, cap for ie8- - .isSealed(object) -> bool, cap for ie8- - .isFrozen(object) -> bool, cap for ie8- - .isExtensible(object) -> bool, cap for ie8- -Array - .isArray(var) -> bool - #slice(start?, end?) -> array, fix for ie7- - #join(string = ',') -> string, fix for ie7- - #indexOf(var, from?) -> int - #lastIndexOf(var, from?) -> int - #every(fn(val, index, @), that) -> bool - #some(fn(val, index, @), that) -> bool - #forEach(fn(val, index, @), that) -> void - #map(fn(val, index, @), that) -> array - #filter(fn(val, index, @), that) -> array - #reduce(fn(memo, val, index, @), memo?) -> var - #reduceRight(fn(memo, val, index, @), memo?) -> var - #sort(fn?) -> @, fixes for some engines -Function - #bind(object, ...args) -> boundFn(...args) -String - #split(separator, limit) -> array - #trim() -> str -RegExp - #toString() -> str -Number - #toFixed(digits) -> string - #toPrecision(precision) -> string -parseInt(str, radix) -> int -parseFloat(str) -> num -Date - .now() -> int - #toISOString() -> string - #toJSON() -> string -``` -[*CommonJS entry points:*](#commonjs) -``` -core-js(/library)/es5 -``` - -### ECMAScript 6 -[*CommonJS entry points:*](#commonjs) -``` -core-js(/library)/es6 -``` -#### ECMAScript 6: Object -Modules [`es6.object.assign`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.object.assign.js), [`es6.object.is`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.object.is.js), [`es6.object.set-prototype-of`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.object.set-prototype-of.js) and [`es6.object.to-string`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.object.to-string.js). - -In ES6 most `Object` static methods should work with primitives. Modules [`es6.object.freeze`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.object.freeze.js), [`es6.object.seal`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.object.seal.js), [`es6.object.prevent-extensions`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.object.prevent-extensions.js), [`es6.object.is-frozen`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.object.is-frozen.js), [`es6.object.is-sealed`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.object.is-sealed.js), [`es6.object.is-extensible`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.object.is-extensible.js), [`es6.object.get-own-property-descriptor`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.object.get-own-property-descriptor.js), [`es6.object.get-prototype-of`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.object.get-prototype-of.js), [`es6.object.keys`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.object.keys.js) and [`es6.object.get-own-property-names`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.object.get-own-property-names.js). - -Just ES5 features: [`es6.object.create`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.object.create.js), [`es6.object.define-property`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.object.define-property.js) and [`es6.object.define-properties`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.object.es6.object.define-properties.js). -```js -Object - .assign(target, ...src) -> target - .is(a, b) -> bool - .setPrototypeOf(target, proto | null) -> target (required __proto__ - IE11+) - .create(object | null, descriptors?) -> object - .getPrototypeOf(var) -> object | null - .defineProperty(object, key, desc) -> target - .defineProperties(object, descriptors) -> target - .getOwnPropertyDescriptor(var, key) -> desc | undefined - .keys(var) -> array - .getOwnPropertyNames(var) -> array - .freeze(var) -> var - .seal(var) -> var - .preventExtensions(var) -> var - .isFrozen(var) -> bool - .isSealed(var) -> bool - .isExtensible(var) -> bool - #toString() -> string, ES6 fix: @@toStringTag support -``` -[*CommonJS entry points:*](#commonjs) -``` -core-js(/library)/es6/object -core-js(/library)/fn/object/assign -core-js(/library)/fn/object/is -core-js(/library)/fn/object/set-prototype-of -core-js(/library)/fn/object/get-prototype-of -core-js(/library)/fn/object/create -core-js(/library)/fn/object/define-property -core-js(/library)/fn/object/define-properties -core-js(/library)/fn/object/get-own-property-descriptor -core-js(/library)/fn/object/keys -core-js(/library)/fn/object/get-own-property-names -core-js(/library)/fn/object/freeze -core-js(/library)/fn/object/seal -core-js(/library)/fn/object/prevent-extensions -core-js(/library)/fn/object/is-frozen -core-js(/library)/fn/object/is-sealed -core-js(/library)/fn/object/is-extensible -core-js/fn/object/to-string -``` -[*Examples*](http://goo.gl/ywdwPz): -```js -var foo = {q: 1, w: 2} - , bar = {e: 3, r: 4} - , baz = {t: 5, y: 6}; -Object.assign(foo, bar, baz); // => foo = {q: 1, w: 2, e: 3, r: 4, t: 5, y: 6} - -Object.is(NaN, NaN); // => true -Object.is(0, -0); // => false -Object.is(42, 42); // => true -Object.is(42, '42'); // => false - -function Parent(){} -function Child(){} -Object.setPrototypeOf(Child.prototype, Parent.prototype); -new Child instanceof Child; // => true -new Child instanceof Parent; // => true - -var O = {}; -O[Symbol.toStringTag] = 'Foo'; -'' + O; // => '[object Foo]' - -Object.keys('qwe'); // => ['0', '1', '2'] -Object.getPrototypeOf('qwe') === String.prototype; // => true -``` -#### ECMAScript 6: Function -Modules [`es6.function.name`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.function.name.js), [`es6.function.has-instance`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.function.has-instance.js). Just ES5: [`es6.function.bind`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.function.bind.js). -```js -Function - #bind(object, ...args) -> boundFn(...args) - #name -> string (IE9+) - #@@hasInstance(var) -> bool -``` -[*CommonJS entry points:*](#commonjs) -``` -core-js/es6/function -core-js/fn/function/name -core-js/fn/function/has-instance -core-js/fn/function/bind -core-js/fn/function/virtual/bind -``` -[*Example*](http://goo.gl/zqu3Wp): -```js -(function foo(){}).name // => 'foo' - -console.log.bind(console, 42)(43); // => 42 43 -``` -#### ECMAScript 6: Array -Modules [`es6.array.from`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.array.from.js), [`es6.array.of`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.array.of.js), [`es6.array.copy-within`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.array.copy-within.js), [`es6.array.fill`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.array.fill.js), [`es6.array.find`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.array.find.js), [`es6.array.find-index`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.array.find-index.js), [`es6.array.iterator`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.array.iterator.js). ES5 features with fixes: [`es6.array.is-array`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.array.is-array.js), [`es6.array.slice`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.array.slice.js), [`es6.array.join`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.array.join.js), [`es6.array.index-of`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.array.index-of.js), [`es6.array.last-index-of`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.array.last-index-of.js), [`es6.array.every`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.array.every.js), [`es6.array.some`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.array.some.js), [`es6.array.for-each`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.array.for-each.js), [`es6.array.map`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.array.map.js), [`es6.array.filter`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.array.filter.js), [`es6.array.reduce`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.array.reduce.js), [`es6.array.reduce-right`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.array.reduce-right.js), [`es6.array.sort`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.array.sort.js). -```js -Array - .from(iterable | array-like, mapFn(val, index)?, that) -> array - .of(...args) -> array - .isArray(var) -> bool - #copyWithin(target = 0, start = 0, end = @length) -> @ - #fill(val, start = 0, end = @length) -> @ - #find(fn(val, index, @), that) -> val - #findIndex(fn(val, index, @), that) -> index | -1 - #values() -> iterator - #keys() -> iterator - #entries() -> iterator - #join(string = ',') -> string, fix for ie7- - #slice(start?, end?) -> array, fix for ie7- - #indexOf(var, from?) -> index | -1 - #lastIndexOf(var, from?) -> index | -1 - #every(fn(val, index, @), that) -> bool - #some(fn(val, index, @), that) -> bool - #forEach(fn(val, index, @), that) -> void - #map(fn(val, index, @), that) -> array - #filter(fn(val, index, @), that) -> array - #reduce(fn(memo, val, index, @), memo?) -> var - #reduceRight(fn(memo, val, index, @), memo?) -> var - #sort(fn?) -> @, invalid arguments fix - #@@iterator() -> iterator (values) - #@@unscopables -> object (cap) -Arguments - #@@iterator() -> iterator (values, available only in core-js methods) -``` -[*CommonJS entry points:*](#commonjs) -``` -core-js(/library)/es6/array -core-js(/library)/fn/array/from -core-js(/library)/fn/array/of -core-js(/library)/fn/array/is-array -core-js(/library)/fn/array/iterator -core-js(/library)/fn/array/copy-within -core-js(/library)/fn/array/fill -core-js(/library)/fn/array/find -core-js(/library)/fn/array/find-index -core-js(/library)/fn/array/values -core-js(/library)/fn/array/keys -core-js(/library)/fn/array/entries -core-js(/library)/fn/array/slice -core-js(/library)/fn/array/join -core-js(/library)/fn/array/index-of -core-js(/library)/fn/array/last-index-of -core-js(/library)/fn/array/every -core-js(/library)/fn/array/some -core-js(/library)/fn/array/for-each -core-js(/library)/fn/array/map -core-js(/library)/fn/array/filter -core-js(/library)/fn/array/reduce -core-js(/library)/fn/array/reduce-right -core-js(/library)/fn/array/sort -core-js(/library)/fn/array/virtual/iterator -core-js(/library)/fn/array/virtual/copy-within -core-js(/library)/fn/array/virtual/fill -core-js(/library)/fn/array/virtual/find -core-js(/library)/fn/array/virtual/find-index -core-js(/library)/fn/array/virtual/values -core-js(/library)/fn/array/virtual/keys -core-js(/library)/fn/array/virtual/entries -core-js(/library)/fn/array/virtual/slice -core-js(/library)/fn/array/virtual/join -core-js(/library)/fn/array/virtual/index-of -core-js(/library)/fn/array/virtual/last-index-of -core-js(/library)/fn/array/virtual/every -core-js(/library)/fn/array/virtual/some -core-js(/library)/fn/array/virtual/for-each -core-js(/library)/fn/array/virtual/map -core-js(/library)/fn/array/virtual/filter -core-js(/library)/fn/array/virtual/reduce -core-js(/library)/fn/array/virtual/reduce-right -core-js(/library)/fn/array/virtual/sort -``` -[*Examples*](http://goo.gl/oaUFUf): -```js -Array.from(new Set([1, 2, 3, 2, 1])); // => [1, 2, 3] -Array.from({0: 1, 1: 2, 2: 3, length: 3}); // => [1, 2, 3] -Array.from('123', Number); // => [1, 2, 3] -Array.from('123', function(it){ - return it * it; -}); // => [1, 4, 9] - -Array.of(1); // => [1] -Array.of(1, 2, 3); // => [1, 2, 3] - -var array = ['a', 'b', 'c']; - -for(var val of array)console.log(val); // => 'a', 'b', 'c' -for(var val of array.values())console.log(val); // => 'a', 'b', 'c' -for(var key of array.keys())console.log(key); // => 0, 1, 2 -for(var [key, val] of array.entries()){ - console.log(key); // => 0, 1, 2 - console.log(val); // => 'a', 'b', 'c' -} - -function isOdd(val){ - return val % 2; -} -[4, 8, 15, 16, 23, 42].find(isOdd); // => 15 -[4, 8, 15, 16, 23, 42].findIndex(isOdd); // => 2 -[4, 8, 15, 16, 23, 42].find(isNaN); // => undefined -[4, 8, 15, 16, 23, 42].findIndex(isNaN); // => -1 - -Array(5).fill(42); // => [42, 42, 42, 42, 42] - -[1, 2, 3, 4, 5].copyWithin(0, 3); // => [4, 5, 3, 4, 5] -``` -#### ECMAScript 6: String -Modules [`es6.string.from-code-point`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.string.from-code-point.js), [`es6.string.raw`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.string.raw.js), [`es6.string.iterator`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.string.iterator.js), [`es6.string.code-point-at`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.string.code-point-at.js), [`es6.string.ends-with`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.string.ends-with.js), [`es6.string.includes`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.string.includes.js), [`es6.string.repeat`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.string.repeat.js), [`es6.string.starts-with`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.string.starts-with.js) and [`es6.string.trim`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.string.trim.js). - -Annex B HTML methods. Ugly, but it's also the part of the spec. Modules [`es6.string.anchor`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.string.anchor.js), [`es6.string.big`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.string.big.js), [`es6.string.blink`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.string.blink.js), [`es6.string.bold`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.string.bold.js), [`es6.string.fixed`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.string.fixed.js), [`es6.string.fontcolor`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.string.fontcolor.js), [`es6.string.fontsize`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.string.fontsize.js), [`es6.string.italics`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.string.italics.js), [`es6.string.link`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.string.link.js), [`es6.string.small`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.string.small.js), [`es6.string.strike`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.string.strike.js), [`es6.string.sub`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.string.sub.js) and [`es6.string.sup`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.string.sup.js). -```js -String - .fromCodePoint(...codePoints) -> str - .raw({raw}, ...substitutions) -> str - #includes(str, from?) -> bool - #startsWith(str, from?) -> bool - #endsWith(str, from?) -> bool - #repeat(num) -> str - #codePointAt(pos) -> uint - #trim() -> str, ES6 fix - #anchor(name) -> str - #big() -> str - #blink() -> str - #bold() -> str - #fixed() -> str - #fontcolor(color) -> str - #fontsize(size) -> str - #italics() -> str - #link(url) -> str - #small() -> str - #strike() -> str - #sub() -> str - #sup() -> str - #@@iterator() -> iterator (code points) -``` -[*CommonJS entry points:*](#commonjs) -``` -core-js(/library)/es6/string -core-js(/library)/fn/string/from-code-point -core-js(/library)/fn/string/raw -core-js(/library)/fn/string/includes -core-js(/library)/fn/string/starts-with -core-js(/library)/fn/string/ends-with -core-js(/library)/fn/string/repeat -core-js(/library)/fn/string/code-point-at -core-js(/library)/fn/string/trim -core-js(/library)/fn/string/anchor -core-js(/library)/fn/string/big -core-js(/library)/fn/string/blink -core-js(/library)/fn/string/bold -core-js(/library)/fn/string/fixed -core-js(/library)/fn/string/fontcolor -core-js(/library)/fn/string/fontsize -core-js(/library)/fn/string/italics -core-js(/library)/fn/string/link -core-js(/library)/fn/string/small -core-js(/library)/fn/string/strike -core-js(/library)/fn/string/sub -core-js(/library)/fn/string/sup -core-js(/library)/fn/string/iterator -core-js(/library)/fn/string/virtual/includes -core-js(/library)/fn/string/virtual/starts-with -core-js(/library)/fn/string/virtual/ends-with -core-js(/library)/fn/string/virtual/repeat -core-js(/library)/fn/string/virtual/code-point-at -core-js(/library)/fn/string/virtual/trim -core-js(/library)/fn/string/virtual/anchor -core-js(/library)/fn/string/virtual/big -core-js(/library)/fn/string/virtual/blink -core-js(/library)/fn/string/virtual/bold -core-js(/library)/fn/string/virtual/fixed -core-js(/library)/fn/string/virtual/fontcolor -core-js(/library)/fn/string/virtual/fontsize -core-js(/library)/fn/string/virtual/italics -core-js(/library)/fn/string/virtual/link -core-js(/library)/fn/string/virtual/small -core-js(/library)/fn/string/virtual/strike -core-js(/library)/fn/string/virtual/sub -core-js(/library)/fn/string/virtual/sup -core-js(/library)/fn/string/virtual/iterator -``` -[*Examples*](http://goo.gl/3UaQ93): -```js -for(var val of 'a𠮷b'){ - console.log(val); // => 'a', '𠮷', 'b' -} - -'foobarbaz'.includes('bar'); // => true -'foobarbaz'.includes('bar', 4); // => false -'foobarbaz'.startsWith('foo'); // => true -'foobarbaz'.startsWith('bar', 3); // => true -'foobarbaz'.endsWith('baz'); // => true -'foobarbaz'.endsWith('bar', 6); // => true - -'string'.repeat(3); // => 'stringstringstring' - -'𠮷'.codePointAt(0); // => 134071 -String.fromCodePoint(97, 134071, 98); // => 'a𠮷b' - -var name = 'Bob'; -String.raw`Hi\n${name}!`; // => 'Hi\\nBob!' (ES6 template string syntax) -String.raw({raw: 'test'}, 0, 1, 2); // => 't0e1s2t' - -'foo'.bold(); // => '<b>foo</b>' -'bar'.anchor('a"b'); // => '<a name="a"b">bar</a>' -'baz'.link('http://example.com'); // => '<a href="http://example.com">baz</a>' -``` -#### ECMAScript 6: RegExp -Modules [`es6.regexp.constructor`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.regexp.constructor.js) and [`es6.regexp.flags`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.regexp.flags.js). - -Support well-known [symbols](#ecmascript-6-symbol) `@@match`, `@@replace`, `@@search` and `@@split`, modules [`es6.regexp.match`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.regexp.match.js), [`es6.regexp.replace`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.regexp.replace.js), [`es6.regexp.search`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.regexp.search.js) and [`es6.regexp.split`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.regexp.split.js). -``` -[new] RegExp(pattern, flags?) -> regexp, ES6 fix: can alter flags (IE9+) - #flags -> str (IE9+) - #toString() -> str, ES6 fixes - #@@match(str) -> array | null - #@@replace(str, replacer) -> string - #@@search(str) -> index - #@@split(str, limit) -> array -String - #match(tpl) -> var, ES6 fix for support @@match - #replace(tpl, replacer) -> var, ES6 fix for support @@replace - #search(tpl) -> var, ES6 fix for support @@search - #split(tpl, limit) -> var, ES6 fix for support @@split, some fixes for old engines -``` -[*CommonJS entry points:*](#commonjs) -``` -core-js/es6/regexp -core-js/fn/regexp/constructor -core-js(/library)/fn/regexp/flags -core-js/fn/regexp/to-string -core-js/fn/regexp/match -core-js/fn/regexp/replace -core-js/fn/regexp/search -core-js/fn/regexp/split -``` -[*Examples*](http://goo.gl/PiJxBD): -```js -RegExp(/./g, 'm'); // => /./m - -/foo/.flags; // => '' -/foo/gim.flags; // => 'gim' - -'foo'.match({[Symbol.match]: _ => 1}); // => 1 -'foo'.replace({[Symbol.replace]: _ => 2}); // => 2 -'foo'.search({[Symbol.search]: _ => 3}); // => 3 -'foo'.split({[Symbol.split]: _ => 4}); // => 4 - -RegExp.prototype.toString.call({source: 'foo', flags: 'bar'}); // => '/foo/bar' -``` -#### ECMAScript 6: Number -Module [`es6.number.constructor`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.number.constructor.js). `Number` constructor support binary and octal literals, [*example*](http://goo.gl/jRd6b3): -```js -Number('0b1010101'); // => 85 -Number('0o7654321'); // => 2054353 -``` -Modules [`es6.number.epsilon`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.number.epsilon.js), [`es6.number.is-finite`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.number.is-finite.js), [`es6.number.is-integer`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.number.is-integer.js), [`es6.number.is-nan`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.number.is-nan.js), [`es6.number.is-safe-integer`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.number.is-safe-integer.js), [`es6.number.max-safe-integer`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.number.max-safe-integer.js), [`es6.number.min-safe-integer`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.number.min-safe-integer.js), [`es6.number.parse-float`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.number.parse-float.js), [`es6.number.parse-int`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.number.parse-int.js), [`es6.number.to-fixed`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.number.to-fixed.js), [`es6.number.to-precision`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.number.to-precision.js), [`es6.parse-int`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.parse-int.js), [`es6.parse-float`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.parse-float.js). -```js -[new] Number(var) -> number | number object - .isFinite(num) -> bool - .isNaN(num) -> bool - .isInteger(num) -> bool - .isSafeInteger(num) -> bool - .parseFloat(str) -> num - .parseInt(str) -> int - .EPSILON -> num - .MAX_SAFE_INTEGER -> int - .MIN_SAFE_INTEGER -> int - #toFixed(digits) -> string, fixes - #toPrecision(precision) -> string, fixes -parseFloat(str) -> num, fixes -parseInt(str) -> int, fixes -``` -[*CommonJS entry points:*](#commonjs) -``` -core-js(/library)/es6/number -core-js/es6/number/constructor -core-js(/library)/fn/number/is-finite -core-js(/library)/fn/number/is-nan -core-js(/library)/fn/number/is-integer -core-js(/library)/fn/number/is-safe-integer -core-js(/library)/fn/number/parse-float -core-js(/library)/fn/number/parse-int -core-js(/library)/fn/number/epsilon -core-js(/library)/fn/number/max-safe-integer -core-js(/library)/fn/number/min-safe-integer -core-js(/library)/fn/number/to-fixed -core-js(/library)/fn/number/to-precision -core-js(/library)/fn/parse-float -core-js(/library)/fn/parse-int -``` -#### ECMAScript 6: Math -Modules [`es6.math.acosh`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.math.acosh.js), [`es6.math.asinh`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.math.asinh.js), [`es6.math.atanh`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.math.atanh.js), [`es6.math.cbrt`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.math.cbrt.js), [`es6.math.clz32`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.math.clz32.js), [`es6.math.cosh`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.math.cosh.js), [`es6.math.expm1`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.math.expm1.js), [`es6.math.fround`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.math.fround.js), [`es6.math.hypot`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.math.hypot.js), [`es6.math.imul`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.math.imul.js), [`es6.math.log10`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.math.log10.js), [`es6.math.log1p`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.math.log1p.js), [`es6.math.log2`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.math.log2.js), [`es6.math.sign`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.math.sign.js), [`es6.math.sinh`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.math.sinh.js), [`es6.math.tanh`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.math.tanh.js), [`es6.math.trunc`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.math.trunc.js). -```js -Math - .acosh(num) -> num - .asinh(num) -> num - .atanh(num) -> num - .cbrt(num) -> num - .clz32(num) -> uint - .cosh(num) -> num - .expm1(num) -> num - .fround(num) -> num - .hypot(...args) -> num - .imul(num, num) -> int - .log1p(num) -> num - .log10(num) -> num - .log2(num) -> num - .sign(num) -> 1 | -1 | 0 | -0 | NaN - .sinh(num) -> num - .tanh(num) -> num - .trunc(num) -> num -``` -[*CommonJS entry points:*](#commonjs) -``` -core-js(/library)/es6/math -core-js(/library)/fn/math/acosh -core-js(/library)/fn/math/asinh -core-js(/library)/fn/math/atanh -core-js(/library)/fn/math/cbrt -core-js(/library)/fn/math/clz32 -core-js(/library)/fn/math/cosh -core-js(/library)/fn/math/expm1 -core-js(/library)/fn/math/fround -core-js(/library)/fn/math/hypot -core-js(/library)/fn/math/imul -core-js(/library)/fn/math/log1p -core-js(/library)/fn/math/log10 -core-js(/library)/fn/math/log2 -core-js(/library)/fn/math/sign -core-js(/library)/fn/math/sinh -core-js(/library)/fn/math/tanh -core-js(/library)/fn/math/trunc -``` -#### ECMAScript 6: Date -Modules [`es6.date.to-string`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.date.to-string.js), ES5 features with fixes: [`es6.date.now`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.date.now.js), [`es6.date.to-iso-string`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.date.to-iso-string.js), [`es6.date.to-json`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.date.to-json.js) and [`es6.date.to-primitive`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.date.to-primitive.js). -```js -Date - .now() -> int - #toISOString() -> string - #toJSON() -> string - #toString() -> string - #@@toPrimitive(hint) -> primitive -``` -[*CommonJS entry points:*](#commonjs) -``` -core-js/es6/date -core-js/fn/date/to-string -core-js(/library)/fn/date/now -core-js(/library)/fn/date/to-iso-string -core-js(/library)/fn/date/to-json -core-js(/library)/fn/date/to-primitive -``` -[*Example*](http://goo.gl/haeHLR): -```js -new Date(NaN).toString(); // => 'Invalid Date' -``` - -#### ECMAScript 6: Promise -Module [`es6.promise`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.promise.js). -```js -new Promise(executor(resolve(var), reject(var))) -> promise - #then(resolved(var), rejected(var)) -> promise - #catch(rejected(var)) -> promise - .resolve(promise | var) -> promise - .reject(var) -> promise - .all(iterable) -> promise - .race(iterable) -> promise -``` -[*CommonJS entry points:*](#commonjs) -``` -core-js(/library)/es6/promise -core-js(/library)/fn/promise -``` -Basic [*example*](http://goo.gl/vGrtUC): -```js -function sleepRandom(time){ - return new Promise(function(resolve, reject){ - setTimeout(resolve, time * 1e3, 0 | Math.random() * 1e3); - }); -} - -console.log('Run'); // => Run -sleepRandom(5).then(function(result){ - console.log(result); // => 869, after 5 sec. - return sleepRandom(10); -}).then(function(result){ - console.log(result); // => 202, after 10 sec. -}).then(function(){ - console.log('immediately after'); // => immediately after - throw Error('Irror!'); -}).then(function(){ - console.log('will not be displayed'); -}).catch(x => console.log(x)); // => => Error: Irror! -``` -`Promise.resolve` and `Promise.reject` [*example*](http://goo.gl/vr8TN3): -```js -Promise.resolve(42).then(x => console.log(x)); // => 42 -Promise.reject(42).catch(x => console.log(x)); // => 42 - -Promise.resolve($.getJSON('/data.json')); // => ES6 promise -``` -`Promise.all` [*example*](http://goo.gl/RdoDBZ): -```js -Promise.all([ - 'foo', - sleepRandom(5), - sleepRandom(15), - sleepRandom(10) // after 15 sec: -]).then(x => console.log(x)); // => ['foo', 956, 85, 382] -``` -`Promise.race` [*example*](http://goo.gl/L8ovkJ): -```js -function timeLimit(promise, time){ - return Promise.race([promise, new Promise(function(resolve, reject){ - setTimeout(reject, time * 1e3, Error('Await > ' + time + ' sec')); - })]); -} - -timeLimit(sleepRandom(5), 10).then(x => console.log(x)); // => 853, after 5 sec. -timeLimit(sleepRandom(15), 10).catch(x => console.log(x)); // Error: Await > 10 sec -``` -ECMAScript 7 [async functions](https://tc39.github.io/ecmascript-asyncawait) [example](http://goo.gl/wnQS4j): -```js -var delay = time => new Promise(resolve => setTimeout(resolve, time)) - -async function sleepRandom(time){ - await delay(time * 1e3); - return 0 | Math.random() * 1e3; -}; -async function sleepError(time, msg){ - await delay(time * 1e3); - throw Error(msg); -}; - -(async () => { - try { - console.log('Run'); // => Run - console.log(await sleepRandom(5)); // => 936, after 5 sec. - var [a, b, c] = await Promise.all([ - sleepRandom(5), - sleepRandom(15), - sleepRandom(10) - ]); - console.log(a, b, c); // => 210 445 71, after 15 sec. - await sleepError(5, 'Irror!'); - console.log('Will not be displayed'); - } catch(e){ - console.log(e); // => Error: 'Irror!', after 5 sec. - } -})(); -``` - -##### Unhandled rejection tracking - -In Node.js, like in native implementation, available events [`unhandledRejection`](https://nodejs.org/api/process.html#process_event_unhandledrejection) and [`rejectionHandled`](https://nodejs.org/api/process.html#process_event_rejectionhandled): -```js -process.on('unhandledRejection', (reason, promise) => console.log('unhandled', reason, promise)); -process.on('rejectionHandled', (promise) => console.log('handled', promise)); - -var p = Promise.reject(42); -// unhandled 42 [object Promise] - -setTimeout(() => p.catch(_ => _), 1e3); -// handled [object Promise] -``` -In a browser on rejection, by default, you will see notify in the console, or you can add a custom handler and a handler on handling unhandled, [*example*](http://goo.gl/Wozskl): -```js -window.onunhandledrejection = e => console.log('unhandled', e.reason, e.promise); -window.onrejectionhandled = e => console.log('handled', e.reason, e.promise); - -var p = Promise.reject(42); -// unhandled 42 [object Promise] - -setTimeout(() => p.catch(_ => _), 1e3); -// handled 42 [object Promise] -``` - -#### ECMAScript 6: Symbol -Module [`es6.symbol`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.symbol.js). -```js -Symbol(description?) -> symbol - .hasInstance -> @@hasInstance - .isConcatSpreadable -> @@isConcatSpreadable - .iterator -> @@iterator - .match -> @@match - .replace -> @@replace - .search -> @@search - .species -> @@species - .split -> @@split - .toPrimitive -> @@toPrimitive - .toStringTag -> @@toStringTag - .unscopables -> @@unscopables - .for(key) -> symbol - .keyFor(symbol) -> key - .useSimple() -> void - .useSetter() -> void -Object - .getOwnPropertySymbols(object) -> array -``` -Also wrapped some methods for correct work with `Symbol` polyfill. -```js -Object - .create(proto | null, descriptors?) -> object - .defineProperty(target, key, desc) -> target - .defineProperties(target, descriptors) -> target - .getOwnPropertyDescriptor(var, key) -> desc | undefined - .getOwnPropertyNames(var) -> array - #propertyIsEnumerable(key) -> bool -JSON - .stringify(target, replacer?, space?) -> string | undefined -``` -[*CommonJS entry points:*](#commonjs) -``` -core-js(/library)/es6/symbol -core-js(/library)/fn/symbol -core-js(/library)/fn/symbol/has-instance -core-js(/library)/fn/symbol/is-concat-spreadable -core-js(/library)/fn/symbol/iterator -core-js(/library)/fn/symbol/match -core-js(/library)/fn/symbol/replace -core-js(/library)/fn/symbol/search -core-js(/library)/fn/symbol/species -core-js(/library)/fn/symbol/split -core-js(/library)/fn/symbol/to-primitive -core-js(/library)/fn/symbol/to-string-tag -core-js(/library)/fn/symbol/unscopables -core-js(/library)/fn/symbol/for -core-js(/library)/fn/symbol/key-for -``` -[*Basic example*](http://goo.gl/BbvWFc): -```js -var Person = (function(){ - var NAME = Symbol('name'); - function Person(name){ - this[NAME] = name; - } - Person.prototype.getName = function(){ - return this[NAME]; - }; - return Person; -})(); - -var person = new Person('Vasya'); -console.log(person.getName()); // => 'Vasya' -console.log(person['name']); // => undefined -console.log(person[Symbol('name')]); // => undefined, symbols are uniq -for(var key in person)console.log(key); // => only 'getName', symbols are not enumerable -``` -`Symbol.for` & `Symbol.keyFor` [*example*](http://goo.gl/0pdJjX): -```js -var symbol = Symbol.for('key'); -symbol === Symbol.for('key'); // true -Symbol.keyFor(symbol); // 'key' -``` -[*Example*](http://goo.gl/mKVOQJ) with methods for getting own object keys: -```js -var O = {a: 1}; -Object.defineProperty(O, 'b', {value: 2}); -O[Symbol('c')] = 3; -Object.keys(O); // => ['a'] -Object.getOwnPropertyNames(O); // => ['a', 'b'] -Object.getOwnPropertySymbols(O); // => [Symbol(c)] -Reflect.ownKeys(O); // => ['a', 'b', Symbol(c)] -``` -##### Caveats when using `Symbol` polyfill: - -* We can't add new primitive type, `Symbol` returns object. -* `Symbol.for` and `Symbol.keyFor` can't be shimmed cross-realm. -* By default, to hide the keys, `Symbol` polyfill defines setter in `Object.prototype`. For this reason, uncontrolled creation of symbols can cause memory leak and the `in` operator is not working correctly with `Symbol` polyfill: `Symbol() in {} // => true`. - -You can disable defining setters in `Object.prototype`. [Example](http://goo.gl/N5UD7J): -```js -Symbol.useSimple(); -var s1 = Symbol('s1') - , o1 = {}; -o1[s1] = true; -for(var key in o1)console.log(key); // => 'Symbol(s1)_t.qamkg9f3q', w/o native Symbol - -Symbol.useSetter(); -var s2 = Symbol('s2') - , o2 = {}; -o2[s2] = true; -for(var key in o2)console.log(key); // nothing -``` -* Currently, `core-js` not adds setters to `Object.prototype` for well-known symbols for correct work something like `Symbol.iterator in foo`. It can cause problems with their enumerability. -* Some problems possible with environment exotic objects (for example, IE `localStorage`). - -#### ECMAScript 6: Collections -`core-js` uses native collections in most case, just fixes methods / constructor, if it's required, and in old environment uses fast polyfill (O(1) lookup). -#### Map -Module [`es6.map`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.map.js). -```js -new Map(iterable (entries) ?) -> map - #clear() -> void - #delete(key) -> bool - #forEach(fn(val, key, @), that) -> void - #get(key) -> val - #has(key) -> bool - #set(key, val) -> @ - #size -> uint - #values() -> iterator - #keys() -> iterator - #entries() -> iterator - #@@iterator() -> iterator (entries) -``` -[*CommonJS entry points:*](#commonjs) -``` -core-js(/library)/es6/map -core-js(/library)/fn/map -``` -[*Examples*](http://goo.gl/GWR7NI): -```js -var a = [1]; - -var map = new Map([['a', 1], [42, 2]]); -map.set(a, 3).set(true, 4); - -console.log(map.size); // => 4 -console.log(map.has(a)); // => true -console.log(map.has([1])); // => false -console.log(map.get(a)); // => 3 -map.forEach(function(val, key){ - console.log(val); // => 1, 2, 3, 4 - console.log(key); // => 'a', 42, [1], true -}); -map.delete(a); -console.log(map.size); // => 3 -console.log(map.get(a)); // => undefined -console.log(Array.from(map)); // => [['a', 1], [42, 2], [true, 4]] - -var map = new Map([['a', 1], ['b', 2], ['c', 3]]); - -for(var [key, val] of map){ - console.log(key); // => 'a', 'b', 'c' - console.log(val); // => 1, 2, 3 -} -for(var val of map.values())console.log(val); // => 1, 2, 3 -for(var key of map.keys())console.log(key); // => 'a', 'b', 'c' -for(var [key, val] of map.entries()){ - console.log(key); // => 'a', 'b', 'c' - console.log(val); // => 1, 2, 3 -} -``` -#### Set -Module [`es6.set`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.set.js). -```js -new Set(iterable?) -> set - #add(key) -> @ - #clear() -> void - #delete(key) -> bool - #forEach(fn(el, el, @), that) -> void - #has(key) -> bool - #size -> uint - #values() -> iterator - #keys() -> iterator - #entries() -> iterator - #@@iterator() -> iterator (values) -``` -[*CommonJS entry points:*](#commonjs) -``` -core-js(/library)/es6/set -core-js(/library)/fn/set -``` -[*Examples*](http://goo.gl/bmhLwg): -```js -var set = new Set(['a', 'b', 'a', 'c']); -set.add('d').add('b').add('e'); -console.log(set.size); // => 5 -console.log(set.has('b')); // => true -set.forEach(function(it){ - console.log(it); // => 'a', 'b', 'c', 'd', 'e' -}); -set.delete('b'); -console.log(set.size); // => 4 -console.log(set.has('b')); // => false -console.log(Array.from(set)); // => ['a', 'c', 'd', 'e'] - -var set = new Set([1, 2, 3, 2, 1]); - -for(var val of set)console.log(val); // => 1, 2, 3 -for(var val of set.values())console.log(val); // => 1, 2, 3 -for(var key of set.keys())console.log(key); // => 1, 2, 3 -for(var [key, val] of set.entries()){ - console.log(key); // => 1, 2, 3 - console.log(val); // => 1, 2, 3 -} -``` -#### WeakMap -Module [`es6.weak-map`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.weak-map.js). -```js -new WeakMap(iterable (entries) ?) -> weakmap - #delete(key) -> bool - #get(key) -> val - #has(key) -> bool - #set(key, val) -> @ -``` -[*CommonJS entry points:*](#commonjs) -``` -core-js(/library)/es6/weak-map -core-js(/library)/fn/weak-map -``` -[*Examples*](http://goo.gl/SILXyw): -```js -var a = [1] - , b = [2] - , c = [3]; - -var wmap = new WeakMap([[a, 1], [b, 2]]); -wmap.set(c, 3).set(b, 4); -console.log(wmap.has(a)); // => true -console.log(wmap.has([1])); // => false -console.log(wmap.get(a)); // => 1 -wmap.delete(a); -console.log(wmap.get(a)); // => undefined - -// Private properties store: -var Person = (function(){ - var names = new WeakMap; - function Person(name){ - names.set(this, name); - } - Person.prototype.getName = function(){ - return names.get(this); - }; - return Person; -})(); - -var person = new Person('Vasya'); -console.log(person.getName()); // => 'Vasya' -for(var key in person)console.log(key); // => only 'getName' -``` -#### WeakSet -Module [`es6.weak-set`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.weak-set.js). -```js -new WeakSet(iterable?) -> weakset - #add(key) -> @ - #delete(key) -> bool - #has(key) -> bool -``` -[*CommonJS entry points:*](#commonjs) -``` -core-js(/library)/es6/weak-set -core-js(/library)/fn/weak-set -``` -[*Examples*](http://goo.gl/TdFbEx): -```js -var a = [1] - , b = [2] - , c = [3]; - -var wset = new WeakSet([a, b, a]); -wset.add(c).add(b).add(c); -console.log(wset.has(b)); // => true -console.log(wset.has([2])); // => false -wset.delete(b); -console.log(wset.has(b)); // => false -``` -##### Caveats when using collections polyfill: - -* Weak-collections polyfill stores values as hidden properties of keys. It works correct and not leak in most cases. However, it is desirable to store a collection longer than its keys. - -#### ECMAScript 6: Typed Arrays -Implementations and fixes `ArrayBuffer`, `DataView`, typed arrays constructors, static and prototype methods. Typed Arrays work only in environments with support descriptors (IE9+), `ArrayBuffer` and `DataView` should work anywhere. - -Modules [`es6.typed.array-buffer`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.typed.array-buffer.js), [`es6.typed.data-view`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.typed.data-view.js), [`es6.typed.int8-array`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.typed.int8-array.js), [`es6.typed.uint8-array`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.typed.uint8-array.js), [`es6.typed.uint8-clamped-array`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.typed.uint8-clamped-array.js), [`es6.typed.int16-array`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.typed.int16-array.js), [`es6.typed.uint16-array`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.typed.uint16-array.js), [`es6.typed.int32-array`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.typed.int32-array.js), [`es6.typed.uint32-array`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.typed.uint32-array.js), [`es6.typed.float32-array`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.typed.float32-array.js) and [`es6.typed.float64-array`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.typed.float64-array.js). -```js -new ArrayBuffer(length) -> buffer - .isView(var) -> bool - #slice(start = 0, end = @length) -> buffer - #byteLength -> uint - -new DataView(buffer, byteOffset = 0, byteLength = buffer.byteLength - byteOffset) -> view - #getInt8(offset) -> int8 - #getUint8(offset) -> uint8 - #getInt16(offset, littleEndian = false) -> int16 - #getUint16(offset, littleEndian = false) -> uint16 - #getInt32(offset, littleEndian = false) -> int32 - #getUint32(offset, littleEndian = false) -> uint32 - #getFloat32(offset, littleEndian = false) -> float32 - #getFloat64(offset, littleEndian = false) -> float64 - #setInt8(offset, value) -> void - #setUint8(offset, value) -> void - #setInt16(offset, value, littleEndian = false) -> void - #setUint16(offset, value, littleEndian = false) -> void - #setInt32(offset, value, littleEndian = false) -> void - #setUint32(offset, value, littleEndian = false) -> void - #setFloat32(offset, value, littleEndian = false) -> void - #setFloat64(offset, value, littleEndian = false) -> void - #buffer -> buffer - #byteLength -> uint - #byteOffset -> uint - -{ - Int8Array, - Uint8Array, - Uint8ClampedArray, - Int16Array, - Uint16Array, - Int32Array, - Uint32Array, - Float32Array, - Float64Array -} - new %TypedArray%(length) -> typed - new %TypedArray%(typed) -> typed - new %TypedArray%(arrayLike) -> typed - new %TypedArray%(iterable) -> typed - new %TypedArray%(buffer, byteOffset = 0, length = (buffer.byteLength - byteOffset) / @BYTES_PER_ELEMENT) -> typed - .BYTES_PER_ELEMENT -> uint - .from(arrayLike | iterable, mapFn(val, index)?, that) -> typed - .of(...args) -> typed - #BYTES_PER_ELEMENT -> uint - #copyWithin(target = 0, start = 0, end = @length) -> @ - #every(fn(val, index, @), that) -> bool - #fill(val, start = 0, end = @length) -> @ - #filter(fn(val, index, @), that) -> typed - #find(fn(val, index, @), that) -> val - #findIndex(fn(val, index, @), that) -> index - #forEach(fn(val, index, @), that) -> void - #indexOf(var, from?) -> int - #join(string = ',') -> string - #lastIndexOf(var, from?) -> int - #map(fn(val, index, @), that) -> typed - #reduce(fn(memo, val, index, @), memo?) -> var - #reduceRight(fn(memo, val, index, @), memo?) -> var - #reverse() -> @ - #set(arrayLike, offset = 0) -> void - #slice(start = 0, end = @length) -> typed - #some(fn(val, index, @), that) -> bool - #sort(fn(a, b)?) -> @ - #subarray(start = 0, end = @length) -> typed - #toString() -> string - #toLocaleString() -> string - #values() -> iterator - #keys() -> iterator - #entries() -> iterator - #@@iterator() -> iterator (values) - #buffer -> buffer - #byteLength -> uint - #byteOffset -> uint - #length -> uint -``` -[*CommonJS entry points:*](#commonjs) -``` -core-js(/library)/es6/typed -core-js(/library)/fn/typed -core-js(/library)/fn/typed/array-buffer -core-js(/library)/fn/typed/data-view -core-js(/library)/fn/typed/int8-array -core-js(/library)/fn/typed/uint8-array -core-js(/library)/fn/typed/uint8-clamped-array -core-js(/library)/fn/typed/int16-array -core-js(/library)/fn/typed/uint16-array -core-js(/library)/fn/typed/int32-array -core-js(/library)/fn/typed/uint32-array -core-js(/library)/fn/typed/float32-array -core-js(/library)/fn/typed/float64-array -``` -[*Examples*](http://goo.gl/yla75z): -```js -new Int32Array(4); // => [0, 0, 0, 0] -new Uint8ClampedArray([1, 2, 3, 666]); // => [1, 2, 3, 255] -new Float32Array(new Set([1, 2, 3, 2, 1])); // => [1, 2, 3] - -var buffer = new ArrayBuffer(8); -var view = new DataView(buffer); -view.setFloat64(0, 123.456, true); -new Uint8Array(buffer.slice(4)); // => [47, 221, 94, 64] - -Int8Array.of(1, 1.5, 5.7, 745); // => [1, 1, 5, -23] -Uint8Array.from([1, 1.5, 5.7, 745]); // => [1, 1, 5, 233] - -var typed = new Uint8Array([1, 2, 3]); - -var a = typed.slice(1); // => [2, 3] -typed.buffer === a.buffer; // => false -var b = typed.subarray(1); // => [2, 3] -typed.buffer === b.buffer; // => true - -typed.filter(it => it % 2); // => [1, 3] -typed.map(it => it * 1.5); // => [1, 3, 4] - -for(var val of typed)console.log(val); // => 1, 2, 3 -for(var val of typed.values())console.log(val); // => 1, 2, 3 -for(var key of typed.keys())console.log(key); // => 0, 1, 2 -for(var [key, val] of typed.entries()){ - console.log(key); // => 0, 1, 2 - console.log(val); // => 1, 2, 3 -} -``` -##### Caveats when using typed arrays: - -* Typed Arrays polyfills works completely how should work by the spec, but because of internal use getter / setters on each instance, is slow and consumes significant memory. However, typed arrays polyfills required mainly for IE9 (and for `Uint8ClampedArray` in IE10 and early IE11), all modern engines have native typed arrays and requires only constructors fixes and methods. -* The current version hasn't special entry points for methods, they can be added only with constructors. It can be added in the future. -* In the `library` version we can't pollute native prototypes, so prototype methods available as constructors static. - -#### ECMAScript 6: Reflect -Modules [`es6.reflect.apply`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.reflect.apply.js), [`es6.reflect.construct`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.reflect.construct.js), [`es6.reflect.define-property`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.reflect.define-property.js), [`es6.reflect.delete-property`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.reflect.delete-property.js), [`es6.reflect.enumerate`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.reflect.enumerate.js), [`es6.reflect.get`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.reflect.get.js), [`es6.reflect.get-own-property-descriptor`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.reflect.get-own-property-descriptor.js), [`es6.reflect.get-prototype-of`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.reflect.get-prototype-of.js), [`es6.reflect.has`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.reflect.has.js), [`es6.reflect.is-extensible`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.reflect.is-extensible.js), [`es6.reflect.own-keys`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.reflect.own-keys.js), [`es6.reflect.prevent-extensions`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.reflect.prevent-extensions.js), [`es6.reflect.set`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.reflect.set.js), [`es6.reflect.set-prototype-of`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es6.reflect.set-prototype-of.js). -```js -Reflect - .apply(target, thisArgument, argumentsList) -> var - .construct(target, argumentsList, newTarget?) -> object - .defineProperty(target, propertyKey, attributes) -> bool - .deleteProperty(target, propertyKey) -> bool - .enumerate(target) -> iterator (removed from the spec and will be removed from core-js@3) - .get(target, propertyKey, receiver?) -> var - .getOwnPropertyDescriptor(target, propertyKey) -> desc - .getPrototypeOf(target) -> object | null - .has(target, propertyKey) -> bool - .isExtensible(target) -> bool - .ownKeys(target) -> array - .preventExtensions(target) -> bool - .set(target, propertyKey, V, receiver?) -> bool - .setPrototypeOf(target, proto) -> bool (required __proto__ - IE11+) -``` -[*CommonJS entry points:*](#commonjs) -``` -core-js(/library)/es6/reflect -core-js(/library)/fn/reflect -core-js(/library)/fn/reflect/apply -core-js(/library)/fn/reflect/construct -core-js(/library)/fn/reflect/define-property -core-js(/library)/fn/reflect/delete-property -core-js(/library)/fn/reflect/enumerate (deprecated and will be removed from the next major release) -core-js(/library)/fn/reflect/get -core-js(/library)/fn/reflect/get-own-property-descriptor -core-js(/library)/fn/reflect/get-prototype-of -core-js(/library)/fn/reflect/has -core-js(/library)/fn/reflect/is-extensible -core-js(/library)/fn/reflect/own-keys -core-js(/library)/fn/reflect/prevent-extensions -core-js(/library)/fn/reflect/set -core-js(/library)/fn/reflect/set-prototype-of -``` -[*Examples*](http://goo.gl/gVT0cH): -```js -var O = {a: 1}; -Object.defineProperty(O, 'b', {value: 2}); -O[Symbol('c')] = 3; -Reflect.ownKeys(O); // => ['a', 'b', Symbol(c)] - -function C(a, b){ - this.c = a + b; -} - -var instance = Reflect.construct(C, [20, 22]); -instance.c; // => 42 -``` - -### ECMAScript 7+ proposals -[The TC39 process.](https://tc39.github.io/process-document/) - -[*CommonJS entry points:*](#commonjs) -``` -core-js(/library)/es7 -core-js(/library)/es7/array -core-js(/library)/es7/global -core-js(/library)/es7/string -core-js(/library)/es7/map -core-js(/library)/es7/set -core-js(/library)/es7/error -core-js(/library)/es7/math -core-js(/library)/es7/system -core-js(/library)/es7/symbol -core-js(/library)/es7/reflect -core-js(/library)/es7/observable -``` -`core-js/stage/4` entry point contains only stage 4 proposals, `core-js/stage/3` - stage 3 and stage 4, etc. -#### Stage 4 proposals - -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/stage/4 -``` -* `{Array, %TypedArray%}#includes` [proposal](https://github.com/tc39/Array.prototype.includes) - module [`es7.array.includes`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.array.includes.js), `%TypedArray%` version in modules from [this section](#ecmascript-6-typed-arrays). -```js -Array - #includes(var, from?) -> bool -{ - Int8Array, - Uint8Array, - Uint8ClampedArray, - Int16Array, - Uint16Array, - Int32Array, - Uint32Array, - Float32Array, - Float64Array -} - #includes(var, from?) -> bool -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/fn/array/includes -``` -[*Examples*](http://goo.gl/2Gq4ma): -```js -[1, 2, 3].includes(2); // => true -[1, 2, 3].includes(4); // => false -[1, 2, 3].includes(2, 2); // => false - -[NaN].indexOf(NaN); // => -1 -[NaN].includes(NaN); // => true -Array(1).indexOf(undefined); // => -1 -Array(1).includes(undefined); // => true -``` -* `Object.values`, `Object.entries` [proposal](https://github.com/tc39/proposal-object-values-entries) - modules [`es7.object.values`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.object.values.js), [`es7.object.entries`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.object.entries.js) -```js -Object - .values(object) -> array - .entries(object) -> array -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/fn/object/values -core-js(/library)/fn/object/entries -``` -[*Examples*](http://goo.gl/6kuGOn): -```js -Object.values({a: 1, b: 2, c: 3}); // => [1, 2, 3] -Object.entries({a: 1, b: 2, c: 3}); // => [['a', 1], ['b', 2], ['c', 3]] - -for(let [key, value] of Object.entries({a: 1, b: 2, c: 3})){ - console.log(key); // => 'a', 'b', 'c' - console.log(value); // => 1, 2, 3 -} -``` -* `Object.getOwnPropertyDescriptors` [proposal](https://github.com/tc39/proposal-object-getownpropertydescriptors) - module [`es7.object.get-own-property-descriptors`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.object.get-own-property-descriptors.js) -```js -Object - .getOwnPropertyDescriptors(object) -> object -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/fn/object/get-own-property-descriptors -``` -*Examples*: -```js -// Shallow object cloning with prototype and descriptors: -var copy = Object.create(Object.getPrototypeOf(O), Object.getOwnPropertyDescriptors(O)); -// Mixin: -Object.defineProperties(target, Object.getOwnPropertyDescriptors(source)); -``` -* `String#padStart`, `String#padEnd` [proposal](https://github.com/tc39/proposal-string-pad-start-end) - modules [`es7.string.pad-start`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.string.pad-start.js), [`es7.string.pad-end`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.string.pad-end.js) -```js -String - #padStart(length, fillStr = ' ') -> string - #padEnd(length, fillStr = ' ') -> string -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/fn/string/pad-start -core-js(/library)/fn/string/pad-end -core-js(/library)/fn/string/virtual/pad-start -core-js(/library)/fn/string/virtual/pad-end -``` -[*Examples*](http://goo.gl/hK5ccv): -```js -'hello'.padStart(10); // => ' hello' -'hello'.padStart(10, '1234'); // => '12341hello' -'hello'.padEnd(10); // => 'hello ' -'hello'.padEnd(10, '1234'); // => 'hello12341' -``` -* `Object#__(define|lookup)[GS]etter__`, [annex B ES2017](https://github.com/tc39/ecma262/pull/381), but we haven't special namespace for that - modules [`es7.object.define-setter`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.object.define-setter.js), [`es7.object.define-getter`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.object.define-getter.js), [`es7.object.lookup-setter`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.object.lookup-setter.js) and [`es7.object.lookup-getter`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.object.lookup-getter.js). -```js -Object - #__defineSetter__(key, fn) -> void - #__defineGetter__(key, fn) -> void - #__lookupSetter__(key) -> fn | void - #__lookupGetter__(key) -> fn | void -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/fn/object/define-getter -core-js(/library)/fn/object/define-setter -core-js(/library)/fn/object/lookup-getter -core-js(/library)/fn/object/lookup-setter -``` - -#### Stage 3 proposals -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/stage/3 -``` -* `global` [proposal](https://github.com/tc39/proposal-global) - modules [`es7.global`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.global.js) and [`es7.system.global`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.system.global.js) (obsolete) -```js -global -> object -System - .global -> object (obsolete) -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/fn/global -core-js(/library)/fn/system/global (obsolete) -``` -[*Examples*](http://goo.gl/gEqMl7): -```js -global.Array === Array; // => true -``` -* `Promise#finally` [proposal](https://github.com/tc39/proposal-promise-finally) - module [`es7.promise.finally`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.promise.finally.js) -```js -Promise - #finally(onFinally()) -> promise -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/fn/promise/finally -``` -[*Examples*](https://goo.gl/AhyBbJ): -```js -Promise.resolve(42).finally(() => console.log('You will see it anyway')); - -Promise.reject(42).finally(() => console.log('You will see it anyway')); - -#### Stage 2 proposals -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/stage/2 -``` -* `String#trimLeft`, `String#trimRight` / `String#trimStart`, `String#trimEnd` [proposal](https://github.com/sebmarkbage/ecmascript-string-left-right-trim) - modules [`es7.string.trim-left`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.string.trim-right.js), [`es7.string.trim-right`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.string.trim-right.js) -```js -String - #trimLeft() -> string - #trimRight() -> string - #trimStart() -> string - #trimEnd() -> string -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/fn/string/trim-start -core-js(/library)/fn/string/trim-end -core-js(/library)/fn/string/trim-left -core-js(/library)/fn/string/trim-right -core-js(/library)/fn/string/virtual/trim-start -core-js(/library)/fn/string/virtual/trim-end -core-js(/library)/fn/string/virtual/trim-left -core-js(/library)/fn/string/virtual/trim-right -``` -[*Examples*](http://goo.gl/Er5lMJ): -```js -' hello '.trimLeft(); // => 'hello ' -' hello '.trimRight(); // => ' hello' -``` -``` -* `Symbol.asyncIterator` for [async iteration proposal](https://github.com/tc39/proposal-async-iteration) - module [`es7.symbol.async-iterator`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.symbol.async-iterator.js) -```js -Symbol - .asyncIterator -> @@asyncIterator -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/fn/symbol/async-iterator -``` - -#### Stage 1 proposals -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/stage/1 -``` -* `Promise.try` [proposal](https://github.com/tc39/proposal-promise-try) - module [`es7.promise.try`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.promise.try.js) -```js -Promise - .try(function()) -> promise -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/fn/promise/try -``` -[*Examples*](https://goo.gl/k5GGRo): -```js -Promise.try(() => 42).then(it => console.log(`Promise, resolved as ${it}`)); - -Promise.try(() => { throw 42; }).catch(it => console.log(`Promise, rejected as ${it}`)); -``` -* `Array#flatten` and `Array#flatMap` [proposal](https://tc39.github.io/proposal-flatMap) - modules [`es7.array.flatten`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.array.flatten.js) and [`es7.array.flat-map`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.array.flat-map.js) -```js -Array - #flatten(depthArg = 1) -> array - #flatMap(fn(val, key, @), that) -> array -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/fn/array/flatten -core-js(/library)/fn/array/flat-map -core-js(/library)/fn/array/virtual/flatten -core-js(/library)/fn/array/virtual/flat-map -``` -[*Examples*](https://goo.gl/jTXsZi): -```js -[1, [2, 3], [4, 5]].flatten(); // => [1, 2, 3, 4, 5] -[1, [2, [3, [4]]], 5].flatten(); // => [1, 2, [3, [4]], 5] -[1, [2, [3, [4]]], 5].flatten(3); // => [1, 2, 3, 4, 5] - -[{a: 1, b: 2}, {a: 3, b: 4}, {a: 5, b: 6}].flatMap(it => [it.a, it.b]); // => [1, 2, 3, 4, 5, 6] -``` -* `.of` and `.from` methods on collection constructors [proposal](https://github.com/tc39/proposal-setmap-offrom) - modules [`es7.set.of`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.set.of.js), [`es7.set.from`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.set.from.js), [`es7.map.of`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.map.of.js), [`es7.map.from`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.map.from.js), [`es7.weak-set.of`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.weak-set.of.js), [`es7.weak-set.from`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.weak-set.from.js), [`es7.weak-map.of`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.weak-map.of.js), [`es7.weak-map.from`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.weak-map.from.js) -```js -Set - .of(...args) -> set - .from(iterable, mapFn(val, index)?, that?) -> set -Map - .of(...args) -> map - .from(iterable, mapFn(val, index)?, that?) -> map -WeakSet - .of(...args) -> weakset - .from(iterable, mapFn(val, index)?, that?) -> weakset -WeakMap - .of(...args) -> weakmap - .from(iterable, mapFn(val, index)?, that?) -> weakmap -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/fn/set/of -core-js(/library)/fn/set/from -core-js(/library)/fn/map/of -core-js(/library)/fn/map/from -core-js(/library)/fn/weak-set/of -core-js(/library)/fn/weak-set/from -core-js(/library)/fn/weak-map/of -core-js(/library)/fn/weak-map/from -``` -[*Examples*](https://goo.gl/mSC7eU): -```js -Set.of(1, 2, 3, 2, 1); // => Set {1, 2, 3} - -Map.from([[1, 2], [3, 4]], ([key, val]) => [key ** 2, val ** 2]); // => Map {1: 4, 9: 16} -``` -* `String#matchAll` [proposal](https://github.com/tc39/String.prototype.matchAll) - module [`es7.string.match-all`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.string.match-all.js) -```js -String - #matchAll(regexp) -> iterator -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/fn/string/match-all -core-js(/library)/fn/string/virtual/match-all -``` -[*Examples*](http://goo.gl/6kp9EB): -```js -for(let [_, d, D] of '1111a2b3cccc'.matchAll(/(\d)(\D)/)){ - console.log(d, D); // => 1 a, 2 b, 3 c -} -``` -* `Observable` [proposal](https://github.com/zenparsing/es-observable) - modules [`es7.observable`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.observable.js) and [`es7.symbol.observable`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.symbol.observable.js) -```js -new Observable(fn) -> observable - #subscribe(observer) -> subscription - #forEach(fn) -> promise - #@@observable() -> @ - .of(...items) -> observable - .from(observable | iterable) -> observable - .@@species -> @ -Symbol - .observable -> @@observable -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/fn/observable -core-js(/library)/fn/symbol/observable -``` -[*Examples*](http://goo.gl/1LDywi): -```js -new Observable(observer => { - observer.next('hello'); - observer.next('world'); - observer.complete(); -}).forEach(it => console.log(it)) - .then(_ => console.log('!')); -``` -* `Math.{clamp, DEG_PER_RAD, degrees, fscale, rad-per-deg, radians, scale}` - [proposal](https://github.com/rwaldron/proposal-math-extensions) - modules - [`es7.math.clamp`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.math.clamp.js), - [`es7.math.DEG_PER_RAD`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.math.DEG_PER_RAD.js), - [`es7.math.degrees`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.math.degrees.js), - [`es7.math.fscale`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.math.fscale.js), - [`es7.math.RAD_PER_DEG`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.math.RAD_PER_DEG.js), - [`es7.math.radians`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.math.radians.js) and - [`es7.math.scale`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.math.scale.js) -```js -Math - .DEG_PER_RAD -> number - .RAD_PER_DEG -> number - .clamp(x, lower, upper) -> number - .degrees(radians) -> number - .fscale(x, inLow, inHigh, outLow, outHigh) -> number - .radians(degrees) -> number - .scale(x, inLow, inHigh, outLow, outHigh) -> number -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/fn/math/clamp -core-js(/library)/fn/math/deg-per-rad -core-js(/library)/fn/math/degrees -core-js(/library)/fn/math/fscale -core-js(/library)/fn/math/rad-per-deg -core-js(/library)/fn/math/radians -core-js(/library)/fn/math/scale -``` -* `Math.signbit` [proposal](http://jfbastien.github.io/papers/Math.signbit.html) - module [`es7.math.signbit`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.math.signbit.js) -```js -Math - .signbit(x) -> bool -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/fn/math/signbit -``` -[*Examples*](http://es6.zloirock.ru/): -```js -Math.signbit(NaN); // => NaN -Math.signbit(1); // => true -Math.signbit(-1); // => false -Math.signbit(0); // => true -Math.signbit(-0); // => false -``` - -#### Stage 0 proposals -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/stage/0 -``` -* `String#at` [proposal](https://github.com/mathiasbynens/String.prototype.at) - module [`es7.string.at`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.string.at.js) -```js -String - #at(index) -> string -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/fn/string/at -core-js(/library)/fn/string/virtual/at -``` -[*Examples*](http://goo.gl/XluXI8): -```js -'a𠮷b'.at(1); // => '𠮷' -'a𠮷b'.at(1).length; // => 2 -``` -* `Map#toJSON`, `Set#toJSON` [proposal](https://github.com/DavidBruant/Map-Set.prototype.toJSON) - modules [`es7.map.to-json`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.map.to-json.js), [`es7.set.to-json`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.set.to-json.js) (rejected and will be removed from `core-js@3`) -```js -Map - #toJSON() -> array (rejected and will be removed from core-js@3) -Set - #toJSON() -> array (rejected and will be removed from core-js@3) -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/fn/map -core-js(/library)/fn/set -``` -* `Error.isError` [proposal](https://github.com/ljharb/proposal-is-error) - module [`es7.error.is-error`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.error.is-error.js) (withdrawn and will be removed from `core-js@3`) -```js -Error - .isError(it) -> bool (withdrawn and will be removed from core-js@3) -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/fn/error/is-error -``` -* `Math.{iaddh, isubh, imulh, umulh}` [proposal](https://gist.github.com/BrendanEich/4294d5c212a6d2254703) - modules [`es7.math.iaddh`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.math.iaddh.js), [`es7.math.isubh`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.math.isubh.js), [`es7.math.imulh`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.math.imulh.js) and [`es7.math.umulh`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.math.umulh.js) -```js -Math - .iaddh(lo0, hi0, lo1, hi1) -> int32 - .isubh(lo0, hi0, lo1, hi1) -> int32 - .imulh(a, b) -> int32 - .umulh(a, b) -> uint32 -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/fn/math/iaddh -core-js(/library)/fn/math/isubh -core-js(/library)/fn/math/imulh -core-js(/library)/fn/math/umulh -``` -* `global.asap`, [TC39 discussion](https://github.com/rwaldron/tc39-notes/blob/master/es6/2014-09/sept-25.md#510-globalasap-for-enqueuing-a-microtask), module [`es7.asap`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.asap.js) -```js -asap(fn) -> void -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/fn/asap -``` -[*Examples*](http://goo.gl/tx3SRK): -```js -asap(() => console.log('called as microtask')); -``` - -#### Pre-stage 0 proposals -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/stage/pre -``` -* `Reflect` metadata [proposal](https://github.com/jonathandturner/decorators/blob/master/specs/metadata.md) - modules [`es7.reflect.define-metadata`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.reflect.define-metadata.js), [`es7.reflect.delete-metadata`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.reflect.delete-metadata.js), [`es7.reflect.get-metadata`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.reflect.get-metadata.js), [`es7.reflect.get-metadata-keys`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.reflect.get-metadata-keys.js), [`es7.reflect.get-own-metadata`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.reflect.get-own-metadata.js), [`es7.reflect.get-own-metadata-keys`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.reflect.get-own-metadata-keys.js), [`es7.reflect.has-metadata`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.reflect.has-metadata.js), [`es7.reflect.has-own-metadata`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.reflect.has-own-metadata.js) and [`es7.reflect.metadata`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/es7.reflect.metadata.js). -```js -Reflect - .defineMetadata(metadataKey, metadataValue, target, propertyKey?) -> void - .getMetadata(metadataKey, target, propertyKey?) -> var - .getOwnMetadata(metadataKey, target, propertyKey?) -> var - .hasMetadata(metadataKey, target, propertyKey?) -> bool - .hasOwnMetadata(metadataKey, target, propertyKey?) -> bool - .deleteMetadata(metadataKey, target, propertyKey?) -> bool - .getMetadataKeys(target, propertyKey?) -> array - .getOwnMetadataKeys(target, propertyKey?) -> array - .metadata(metadataKey, metadataValue) -> decorator(target, targetKey?) -> void -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/fn/reflect/define-metadata -core-js(/library)/fn/reflect/delete-metadata -core-js(/library)/fn/reflect/get-metadata -core-js(/library)/fn/reflect/get-metadata-keys -core-js(/library)/fn/reflect/get-own-metadata -core-js(/library)/fn/reflect/get-own-metadata-keys -core-js(/library)/fn/reflect/has-metadata -core-js(/library)/fn/reflect/has-own-metadata -core-js(/library)/fn/reflect/metadata -``` -[*Examples*](http://goo.gl/KCo3PS): -```js -var O = {}; -Reflect.defineMetadata('foo', 'bar', O); -Reflect.ownKeys(O); // => [] -Reflect.getOwnMetadataKeys(O); // => ['foo'] -Reflect.getOwnMetadata('foo', O); // => 'bar' -``` - -### Web standards -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/web -``` -#### setTimeout / setInterval -Module [`web.timers`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/web.timers.js). Additional arguments fix for IE9-. -```js -setTimeout(fn(...args), time, ...args) -> id -setInterval(fn(...args), time, ...args) -> id -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/web/timers -core-js(/library)/fn/set-timeout -core-js(/library)/fn/set-interval -``` -```js -// Before: -setTimeout(log.bind(null, 42), 1000); -// After: -setTimeout(log, 1000, 42); -``` -#### setImmediate -Module [`web.immediate`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/web.immediate.js). [`setImmediate` proposal](https://developer.mozilla.org/en-US/docs/Web/API/Window.setImmediate) polyfill. -```js -setImmediate(fn(...args), ...args) -> id -clearImmediate(id) -> void -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/web/immediate -core-js(/library)/fn/set-immediate -core-js(/library)/fn/clear-immediate -``` -[*Examples*](http://goo.gl/6nXGrx): -```js -setImmediate(function(arg1, arg2){ - console.log(arg1, arg2); // => Message will be displayed with minimum delay -}, 'Message will be displayed', 'with minimum delay'); - -clearImmediate(setImmediate(function(){ - console.log('Message will not be displayed'); -})); -``` -#### Iterable DOM collections -Some DOM collections should have [iterable interface](https://heycam.github.io/webidl/#idl-iterable) or should be [inherited from `Array`](https://heycam.github.io/webidl/#LegacyArrayClass). That mean they should have `keys`, `values`, `entries` and `@@iterator` methods for iteration. So add them. Module [`web.dom.iterable`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/web.dom.iterable.js): -```js -{ - CSSRuleList, - CSSStyleDeclaration, - CSSValueList, - ClientRectList, - DOMRectList, - DOMStringList, - DOMTokenList, - DataTransferItemList, - FileList, - HTMLAllCollection, - HTMLCollection, - HTMLFormElement, - HTMLSelectElement, - MediaList, - MimeTypeArray, - NamedNodeMap, - NodeList, - PaintRequestList, - Plugin, - PluginArray, - SVGLengthList, - SVGNumberList, - SVGPathSegList, - SVGPointList, - SVGStringList, - SVGTransformList, - SourceBufferList, - StyleSheetList, - TextTrackCueList, - TextTrackList, - TouchList -} - #@@iterator() -> iterator (values) - -{ - DOMTokenList, - NodeList -} - #values() -> iterator - #keys() -> iterator - #entries() -> iterator -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/web/dom-collections -core-js(/library)/fn/dom-collections/iterator -``` -[*Examples*](http://goo.gl/lfXVFl): -```js -for(var {id} of document.querySelectorAll('*')){ - if(id)console.log(id); -} - -for(var [index, {id}] of document.querySelectorAll('*').entries()){ - if(id)console.log(index, id); -} -``` -### Non-standard -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/core -``` -#### Object -Modules [`core.object.is-object`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/core.object.is-object.js), [`core.object.classof`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/core.object.classof.js), [`core.object.define`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/core.object.define.js), [`core.object.make`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/core.object.make.js). -```js -Object - .isObject(var) -> bool - .classof(var) -> string - .define(target, mixin) -> target - .make(proto | null, mixin?) -> object -``` - -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/core/object -core-js(/library)/fn/object/is-object -core-js(/library)/fn/object/define -core-js(/library)/fn/object/make -``` -Object classify [*examples*](http://goo.gl/YZQmGo): -```js -Object.isObject({}); // => true -Object.isObject(isNaN); // => true -Object.isObject(null); // => false - -var classof = Object.classof; - -classof(null); // => 'Null' -classof(undefined); // => 'Undefined' -classof(1); // => 'Number' -classof(true); // => 'Boolean' -classof('string'); // => 'String' -classof(Symbol()); // => 'Symbol' - -classof(new Number(1)); // => 'Number' -classof(new Boolean(true)); // => 'Boolean' -classof(new String('string')); // => 'String' - -var fn = function(){} - , list = (function(){return arguments})(1, 2, 3); - -classof({}); // => 'Object' -classof(fn); // => 'Function' -classof([]); // => 'Array' -classof(list); // => 'Arguments' -classof(/./); // => 'RegExp' -classof(new TypeError); // => 'Error' - -classof(new Set); // => 'Set' -classof(new Map); // => 'Map' -classof(new WeakSet); // => 'WeakSet' -classof(new WeakMap); // => 'WeakMap' -classof(new Promise(fn)); // => 'Promise' - -classof([].values()); // => 'Array Iterator' -classof(new Set().values()); // => 'Set Iterator' -classof(new Map().values()); // => 'Map Iterator' - -classof(Math); // => 'Math' -classof(JSON); // => 'JSON' - -function Example(){} -Example.prototype[Symbol.toStringTag] = 'Example'; - -classof(new Example); // => 'Example' -``` -`Object.define` and `Object.make` [*examples*](http://goo.gl/rtpD5Z): -```js -// Before: -Object.defineProperty(target, 'c', { - enumerable: true, - configurable: true, - get: function(){ - return this.a + this.b; - } -}); - -// After: -Object.define(target, { - get c(){ - return this.a + this.b; - } -}); - -// Shallow object cloning with prototype and descriptors: -var copy = Object.make(Object.getPrototypeOf(src), src); - -// Simple inheritance: -function Vector2D(x, y){ - this.x = x; - this.y = y; -} -Object.define(Vector2D.prototype, { - get xy(){ - return Math.hypot(this.x, this.y); - } -}); -function Vector3D(x, y, z){ - Vector2D.apply(this, arguments); - this.z = z; -} -Vector3D.prototype = Object.make(Vector2D.prototype, { - constructor: Vector3D, - get xyz(){ - return Math.hypot(this.x, this.y, this.z); - } -}); - -var vector = new Vector3D(9, 12, 20); -console.log(vector.xy); // => 15 -console.log(vector.xyz); // => 25 -vector.y++; -console.log(vector.xy); // => 15.811388300841896 -console.log(vector.xyz); // => 25.495097567963924 -``` -#### Dict -Module [`core.dict`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/core.dict.js). Based on [TC39 discuss](https://github.com/rwaldron/tc39-notes/blob/master/es6/2012-11/nov-29.md#collection-apis-review) / [strawman](http://wiki.ecmascript.org/doku.php?id=harmony:modules_standard#dictionaries). -```js -[new] Dict(iterable (entries) | object ?) -> dict - .isDict(var) -> bool - .values(object) -> iterator - .keys(object) -> iterator - .entries(object) -> iterator (entries) - .has(object, key) -> bool - .get(object, key) -> val - .set(object, key, value) -> object - .forEach(object, fn(val, key, @), that) -> void - .map(object, fn(val, key, @), that) -> new @ - .mapPairs(object, fn(val, key, @), that) -> new @ - .filter(object, fn(val, key, @), that) -> new @ - .some(object, fn(val, key, @), that) -> bool - .every(object, fn(val, key, @), that) -> bool - .find(object, fn(val, key, @), that) -> val - .findKey(object, fn(val, key, @), that) -> key - .keyOf(object, var) -> key - .includes(object, var) -> bool - .reduce(object, fn(memo, val, key, @), memo?) -> var -``` - -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/core/dict -core-js(/library)/fn/dict -``` -`Dict` create object without prototype from iterable or simple object. - -[*Examples*](http://goo.gl/pnp8Vr): -```js -var map = new Map([['a', 1], ['b', 2], ['c', 3]]); - -Dict(); // => {__proto__: null} -Dict({a: 1, b: 2, c: 3}); // => {__proto__: null, a: 1, b: 2, c: 3} -Dict(map); // => {__proto__: null, a: 1, b: 2, c: 3} -Dict([1, 2, 3].entries()); // => {__proto__: null, 0: 1, 1: 2, 2: 3} - -var dict = Dict({a: 42}); -dict instanceof Object; // => false -dict.a; // => 42 -dict.toString; // => undefined -'a' in dict; // => true -'hasOwnProperty' in dict; // => false - -Dict.isDict({}); // => false -Dict.isDict(Dict()); // => true -``` -`Dict.keys`, `Dict.values` and `Dict.entries` returns iterators for objects. - -[*Examples*](http://goo.gl/xAvECH): -```js -var dict = {a: 1, b: 2, c: 3}; - -for(var key of Dict.keys(dict))console.log(key); // => 'a', 'b', 'c' - -for(var val of Dict.values(dict))console.log(val); // => 1, 2, 3 - -for(var [key, val] of Dict.entries(dict)){ - console.log(key); // => 'a', 'b', 'c' - console.log(val); // => 1, 2, 3 -} - -new Map(Dict.entries(dict)); // => Map {a: 1, b: 2, c: 3} -``` -Basic dict operations for objects with prototype [*examples*](http://goo.gl/B28UnG): -```js -'q' in {q: 1}; // => true -'toString' in {}; // => true - -Dict.has({q: 1}, 'q'); // => true -Dict.has({}, 'toString'); // => false - -({q: 1})['q']; // => 1 -({}).toString; // => function toString(){ [native code] } - -Dict.get({q: 1}, 'q'); // => 1 -Dict.get({}, 'toString'); // => undefined - -var O = {}; -O['q'] = 1; -O['q']; // => 1 -O['__proto__'] = {w: 2}; -O['__proto__']; // => {w: 2} -O['w']; // => 2 - -var O = {}; -Dict.set(O, 'q', 1); -O['q']; // => 1 -Dict.set(O, '__proto__', {w: 2}); -O['__proto__']; // => {w: 2} -O['w']; // => undefined -``` -Other methods of `Dict` module are static equivalents of `Array.prototype` methods for dictionaries. - -[*Examples*](http://goo.gl/xFi1RH): -```js -var dict = {a: 1, b: 2, c: 3}; - -Dict.forEach(dict, console.log, console); -// => 1, 'a', {a: 1, b: 2, c: 3} -// => 2, 'b', {a: 1, b: 2, c: 3} -// => 3, 'c', {a: 1, b: 2, c: 3} - -Dict.map(dict, function(it){ - return it * it; -}); // => {a: 1, b: 4, c: 9} - -Dict.mapPairs(dict, function(val, key){ - if(key != 'b')return [key + key, val * val]; -}); // => {aa: 1, cc: 9} - -Dict.filter(dict, function(it){ - return it % 2; -}); // => {a: 1, c: 3} - -Dict.some(dict, function(it){ - return it === 2; -}); // => true - -Dict.every(dict, function(it){ - return it === 2; -}); // => false - -Dict.find(dict, function(it){ - return it > 2; -}); // => 3 -Dict.find(dict, function(it){ - return it > 4; -}); // => undefined - -Dict.findKey(dict, function(it){ - return it > 2; -}); // => 'c' -Dict.findKey(dict, function(it){ - return it > 4; -}); // => undefined - -Dict.keyOf(dict, 2); // => 'b' -Dict.keyOf(dict, 4); // => undefined - -Dict.includes(dict, 2); // => true -Dict.includes(dict, 4); // => false - -Dict.reduce(dict, function(memo, it){ - return memo + it; -}); // => 6 -Dict.reduce(dict, function(memo, it){ - return memo + it; -}, ''); // => '123' -``` -#### Partial application -Module [`core.function.part`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/core.function.part.js). -```js -Function - #part(...args | _) -> fn(...args) -``` - -[*CommonJS entry points:*](#commonjs) -```js -core-js/core/function -core-js(/library)/fn/function/part -core-js(/library)/fn/function/virtual/part -core-js(/library)/fn/_ -``` -`Function#part` partial apply function without `this` binding. Uses global variable `_` (`core._` for builds without global namespace pollution) as placeholder and not conflict with `Underscore` / `LoDash`. - -[*Examples*](http://goo.gl/p9ZJ8K): -```js -var fn1 = log.part(1, 2); -fn1(3, 4); // => 1, 2, 3, 4 - -var fn2 = log.part(_, 2, _, 4); -fn2(1, 3); // => 1, 2, 3, 4 - -var fn3 = log.part(1, _, _, 4); -fn3(2, 3); // => 1, 2, 3, 4 - -fn2(1, 3, 5); // => 1, 2, 3, 4, 5 -fn2(1); // => 1, 2, undefined, 4 -``` -#### Number Iterator -Module [`core.number.iterator`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/core.number.iterator.js). -```js -Number - #@@iterator() -> iterator -``` - -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/core/number -core-js(/library)/fn/number/iterator -core-js(/library)/fn/number/virtual/iterator -``` -[*Examples*](http://goo.gl/o45pCN): -```js -for(var i of 3)console.log(i); // => 0, 1, 2 - -[...10]; // => [0, 1, 2, 3, 4, 5, 6, 7, 8, 9] - -Array.from(10, Math.random); // => [0.9817775336559862, 0.02720663254149258, ...] - -Array.from(10, function(it){ - return this + it * it; -}, .42); // => [0.42, 1.42, 4.42, 9.42, 16.42, 25.42, 36.42, 49.42, 64.42, 81.42] -``` -#### Escaping strings -Modules [`core.regexp.escape`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/core.regexp.escape.js), [`core.string.escape-html`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/core.string.escape-html.js) and [`core.string.unescape-html`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/core.string.unescape-html.js). -```js -RegExp - .escape(str) -> str -String - #escapeHTML() -> str - #unescapeHTML() -> str -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/core/regexp -core-js(/library)/core/string -core-js(/library)/fn/regexp/escape -core-js(/library)/fn/string/escape-html -core-js(/library)/fn/string/unescape-html -core-js(/library)/fn/string/virtual/escape-html -core-js(/library)/fn/string/virtual/unescape-html -``` -[*Examples*](http://goo.gl/6bOvsQ): -```js -RegExp.escape('Hello, []{}()*+?.\\^$|!'); // => 'Hello, \[\]\{\}\(\)\*\+\?\.\\\^\$\|!' - -'<script>doSomething();</script>'.escapeHTML(); // => '<script>doSomething();</script>' -'<script>doSomething();</script>'.unescapeHTML(); // => '<script>doSomething();</script>' -``` -#### delay -Module [`core.delay`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/core.delay.js). [Promise](#ecmascript-6-promise)-returning delay function, [esdiscuss](https://esdiscuss.org/topic/promise-returning-delay-function). -```js -delay(ms) -> promise -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/core/delay -core-js(/library)/fn/delay -``` -[*Examples*](http://goo.gl/lbucba): -```js -delay(1e3).then(() => console.log('after 1 sec')); - -(async () => { - await delay(3e3); - console.log('after 3 sec'); - - while(await delay(3e3))console.log('each 3 sec'); -})(); -``` -#### Helpers for iterators -Modules [`core.is-iterable`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/core.is-iterable.js), [`core.get-iterator`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/core.get-iterator.js), [`core.get-iterator-method`](https://github.com/zloirock/core-js/blob/v2.5.7/modules/core.get-iterator-method.js) - helpers for check iterability / get iterator in the `library` version or, for example, for `arguments` object: -```js -core - .isIterable(var) -> bool - .getIterator(iterable) -> iterator - .getIteratorMethod(var) -> function | undefined -``` -[*CommonJS entry points:*](#commonjs) -```js -core-js(/library)/fn/is-iterable -core-js(/library)/fn/get-iterator -core-js(/library)/fn/get-iterator-method -``` -[*Examples*](http://goo.gl/SXsM6D): -```js -var list = (function(){ - return arguments; -})(1, 2, 3); - -console.log(core.isIterable(list)); // true; - -var iter = core.getIterator(list); -console.log(iter.next().value); // 1 -console.log(iter.next().value); // 2 -console.log(iter.next().value); // 3 -console.log(iter.next().value); // undefined - -core.getIterator({}); // TypeError: [object Object] is not iterable! - -var iterFn = core.getIteratorMethod(list); -console.log(typeof iterFn); // 'function' -var iter = iterFn.call(list); -console.log(iter.next().value); // 1 -console.log(iter.next().value); // 2 -console.log(iter.next().value); // 3 -console.log(iter.next().value); // undefined - -console.log(core.getIteratorMethod({})); // undefined -``` - -## Missing polyfills -- ES5 `JSON` is missing now only in IE7- and never will it be added to `core-js`, if you need it in these old browsers, many implementations are available, for example, [json3](https://github.com/bestiejs/json3). -- ES6 `String#normalize` is not a very useful feature, but this polyfill will be very large. If you need it, you can use [unorm](https://github.com/walling/unorm/). -- ES6 `Proxy` can't be polyfilled, but for Node.js / Chromium with additional flags you can try [harmony-reflect](https://github.com/tvcutsem/harmony-reflect) for adapt old style `Proxy` API to final ES6 version. -- ES6 logic for `@@isConcatSpreadable` and `@@species` (in most places) can be polyfilled without problems, but it will cause a serious slowdown in popular cases in some engines. It will be polyfilled when it will be implemented in modern engines. -- ES7 `SIMD`. `core-js` doesn't add polyfill of this feature because of large size and some other reasons. You can use [this polyfill](https://github.com/tc39/ecmascript_simd/blob/master/src/ecmascript_simd.js). -- `window.fetch` is not a cross-platform feature, in some environments it makes no sense. For this reason, I don't think it should be in `core-js`. Looking at a large number of requests it *may be* added in the future. Now you can use, for example, [this polyfill](https://github.com/github/fetch). -- ECMA-402 `Intl` is missed because of size. You can use [this polyfill](https://github.com/andyearnshaw/Intl.js/). |