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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](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-symbol-constructor)
### 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](http://people.mozilla.org/~jorendorff/es6-draft.html#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 [](https://travis-ci.org/medikoo/es6-symbol)
$ npm test
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