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# es6-symbol
## ECMAScript 6 Symbol polyfill
For more information about symbols see following links
- [Symbols in ECMAScript 6 by Axel Rauschmayer](http://www.2ality.com/2014/12/es6-symbols.html)
- [MDN Documentation](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Symbol)
- [Specification](https://tc39.github.io/ecma262/#sec-symbol-objects)
### Limitations
Underneath it uses real string property names which can easily be retrieved, however accidental collision with other property names is unlikely.
### Usage
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:
```javascript
var Symbol = require("es6-symbol");
```
If you want to make sure your environment implements `Symbol` globally, do:
```javascript
require("es6-symbol/implement");
```
If you strictly want to use polyfill even if native `Symbol` exists (hard to find a good reason for that), do:
```javascript
var Symbol = require("es6-symbol/polyfill");
```
#### API
Best is to refer to [specification](https://tc39.github.io/ecma262/#sec-symbol-objects). Still if you want quick look, follow examples:
```javascript
var Symbol = require("es6-symbol");
var symbol = Symbol("My custom symbol");
var x = {};
x[symbol] = "foo";
console.log(x[symbol]);
("foo");
// Detect iterable:
var iterator, result;
if (possiblyIterable[Symbol.iterator]) {
iterator = possiblyIterable[Symbol.iterator]();
result = iterator.next();
while (!result.done) {
console.log(result.value);
result = iterator.next();
}
}
```
### Installation
#### NPM
In your project path:
$ npm install es6-symbol
##### Browser
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/)
## Tests
$ npm test
## Security contact information
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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[nix-build-image]: https://semaphoreci.com/api/v1/medikoo-org/es6-symbol/branches/master/shields_badge.svg
[nix-build-url]: https://semaphoreci.com/medikoo-org/es6-symbol
[win-build-image]: https://ci.appveyor.com/api/projects/status/1s743lt3el278anj?svg=true
[win-build-url]: https://ci.appveyor.com/project/medikoo/es6-symbol
[transpilation-image]: https://img.shields.io/badge/transpilation-free-brightgreen.svg
[npm-image]: https://img.shields.io/npm/v/es6-symbol.svg
[npm-url]: https://www.npmjs.com/package/es6-symbol