time-to-botec/squiggle/node_modules/@stdlib/symbol/iterator/README.md

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# Iterator Symbol

> Iterator [symbol][mdn-symbol] which specifies the default iterator for an object.

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## Usage

```javascript
var IteratorSymbol = require( '@stdlib/symbol/iterator' );
```

#### IteratorSymbol

Iterator [`symbol`][mdn-symbol] which specifies the default iterator for an object.

```javascript
var s = typeof IteratorSymbol;
// e.g., returns 'symbol'
```

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## Notes

-   The [symbol][mdn-symbol] is only supported in environments which support [symbols][mdn-symbol]. In non-supporting environments, the value is `null`.

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## Examples

<!-- eslint no-undef: "error" -->

```javascript
var IteratorSymbol = require( '@stdlib/symbol/iterator' );

var obj;
var v;

function iterator() {
    var iter;
    var i;

    i = -1;

    iter = {};
    iter.next = next;
    iter.return = done;

    if ( IteratorSymbol ) {
        // Allow the iterator to work with `for...of`:
        iter[ IteratorSymbol ] = iterator;
    }
    return iter;

    function next() {
        i += 1;
        return {
            'value': i,
            'done': false
        };
    }

    function done( value ) {
        if ( arguments.length === 0 ) {
            return {
                'done': true
            };
        }
        return {
            'value': value,
            'done': true
        };
    }
}

obj = iterator();
while ( v === void 0 || ( v.value < 10 && v.done === false ) ) {
    v = obj.next();
    console.log( v.value );
}
```

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[mdn-symbol]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Symbol

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