105 lines
3.2 KiB
Markdown
105 lines
3.2 KiB
Markdown
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[![Build status][nix-build-image]][nix-build-url]
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[![Windows status][win-build-image]][win-build-url]
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![Transpilation status][transpilation-image]
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[![npm version][npm-image]][npm-url]
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# es6-symbol
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## ECMAScript 6 Symbol polyfill
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For more information about symbols see following links
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- [Symbols in ECMAScript 6 by Axel Rauschmayer](http://www.2ality.com/2014/12/es6-symbols.html)
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- [MDN Documentation](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Symbol)
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- [Specification](https://tc39.github.io/ecma262/#sec-symbol-objects)
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### Limitations
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Underneath it uses real string property names which can easily be retrieved, however accidental collision with other property names is unlikely.
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### Usage
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If you'd like to use native version when it exists and fallback to [ponyfill](https://ponyfill.com) if it doesn't, use _es6-symbol_ as following:
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```javascript
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var Symbol = require("es6-symbol");
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```
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If you want to make sure your environment implements `Symbol` globally, do:
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```javascript
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require("es6-symbol/implement");
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```
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If you strictly want to use polyfill even if native `Symbol` exists (hard to find a good reason for that), do:
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```javascript
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var Symbol = require("es6-symbol/polyfill");
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```
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#### API
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Best is to refer to [specification](https://tc39.github.io/ecma262/#sec-symbol-objects). Still if you want quick look, follow examples:
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```javascript
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var Symbol = require("es6-symbol");
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var symbol = Symbol("My custom symbol");
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var x = {};
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x[symbol] = "foo";
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console.log(x[symbol]);
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("foo");
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// Detect iterable:
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var iterator, result;
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if (possiblyIterable[Symbol.iterator]) {
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iterator = possiblyIterable[Symbol.iterator]();
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result = iterator.next();
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while (!result.done) {
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console.log(result.value);
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result = iterator.next();
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}
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}
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```
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### Installation
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#### NPM
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In your project path:
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$ npm install es6-symbol
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##### Browser
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To port it to Browser or any other (non CJS) environment, use your favorite CJS bundler. No favorite yet? Try: [Browserify](http://browserify.org/), [Webmake](https://github.com/medikoo/modules-webmake) or [Webpack](http://webpack.github.io/)
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## Tests
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$ npm test
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## Security contact information
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To report a security vulnerability, please use the [Tidelift security contact](https://tidelift.com/security). Tidelift will coordinate the fix and disclosure.
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---
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<div align="center">
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<b>
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<a href="https://tidelift.com/subscription/pkg/npm-es6-symbol?utm_source=npm-es6-symbol&utm_medium=referral&utm_campaign=readme">Get professional support for d with a Tidelift subscription</a>
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</b>
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<br>
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<sub>
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Tidelift helps make open source sustainable for maintainers while giving companies<br>assurances about security, maintenance, and licensing for their dependencies.
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</sub>
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</div>
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[nix-build-image]: https://semaphoreci.com/api/v1/medikoo-org/es6-symbol/branches/master/shields_badge.svg
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[nix-build-url]: https://semaphoreci.com/medikoo-org/es6-symbol
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[win-build-image]: https://ci.appveyor.com/api/projects/status/1s743lt3el278anj?svg=true
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[win-build-url]: https://ci.appveyor.com/project/medikoo/es6-symbol
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[transpilation-image]: https://img.shields.io/badge/transpilation-free-brightgreen.svg
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[npm-image]: https://img.shields.io/npm/v/es6-symbol.svg
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[npm-url]: https://www.npmjs.com/package/es6-symbol
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