npm package: @stdlib/symbol-iterator
Description: Symbol iterator.
Author: The Stdlib Authors
Latest version: 0.2.3

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<details>
  <summary>
    About stdlib...
  </summary>
  <p>We believe in a future in which the web is a preferred environment for numerical computation. To help realize this future, we've built stdlib. stdlib is a standard library, with an emphasis on numerical and scientific computation, written in JavaScript (and C) for execution in browsers and in Node.js.</p>
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</details>

# IteratorSymbol

[![NPM version][npm-image]][npm-url] [![Build Status][test-image]][test-url] [![Coverage Status][coverage-image]][coverage-url] <!-- [![dependencies][dependencies-image]][dependencies-url] -->

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

<!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->

<section class="intro">

</section>

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<!-- Package usage documentation. -->

<section class="installation">

## Installation

```bash
npm install @stdlib/symbol-iterator
```

</section>

<section class="usage">

## 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'
```

</section>

<!-- /.usage -->

<!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="notes">

## Notes

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

</section>

<!-- /.notes -->

<!-- Package usage examples. -->

<section class="examples">

## Examples

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

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

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

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
        };
    }
}

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

</section>

<!-- /.examples -->

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<section class="references">

</section>

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<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->

<section class="related">

* * *

## See Also

-   <span class="package-name">[`@stdlib/symbol-ctor`][@stdlib/symbol/ctor]</span><span class="delimiter">: </span><span class="description">symbols.</span>

</section>

<!-- /.related -->

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<section class="main-repo" >

* * *

## Notice

This package is part of [stdlib][stdlib], a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop [stdlib][stdlib], see the main project [repository][stdlib].

#### Community

[![Chat][chat-image]][chat-url]

---

## License

See [LICENSE][stdlib-license].


## Copyright

Copyright &copy; 2016-2026. The Stdlib [Authors][stdlib-authors].

</section>

<!-- /.stdlib -->

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<section class="links">

[npm-image]: http://img.shields.io/npm/v/@stdlib/symbol-iterator.svg
[npm-url]: https://npmjs.org/package/@stdlib/symbol-iterator

[test-image]: https://github.com/stdlib-js/symbol-iterator/actions/workflows/test.yml/badge.svg?branch=v0.2.3
[test-url]: https://github.com/stdlib-js/symbol-iterator/actions/workflows/test.yml?query=branch:v0.2.3

[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/symbol-iterator/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/symbol-iterator?branch=main

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[stdlib]: https://github.com/stdlib-js/stdlib

[stdlib-authors]: https://github.com/stdlib-js/stdlib/graphs/contributors

[umd]: https://github.com/umdjs/umd
[es-module]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules

[deno-url]: https://github.com/stdlib-js/symbol-iterator/tree/deno
[deno-readme]: https://github.com/stdlib-js/symbol-iterator/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/symbol-iterator/tree/umd
[umd-readme]: https://github.com/stdlib-js/symbol-iterator/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/symbol-iterator/tree/esm
[esm-readme]: https://github.com/stdlib-js/symbol-iterator/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/symbol-iterator/blob/main/branches.md

[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/symbol-iterator/main/LICENSE

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

<!-- <related-links> -->

[@stdlib/symbol/ctor]: https://www.npmjs.com/package/@stdlib/symbol-ctor

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</section>

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