npm package: @stdlib/utils-identity-function
Description: Identity function.
Author: The Stdlib Authors
Latest version: 0.2.3

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# Identity Function

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

> Identity function.

<section class="installation">

## Installation

```bash
npm install @stdlib/utils-identity-function
```

</section>

<section class="usage">

## Usage

```javascript
var identity = require( '@stdlib/utils-identity-function' );
```

#### identity( x )

Returns `x`.

```javascript
var v = identity( 3.14 );
// returns 3.14

var input = [];
var output = identity( input );
var bool = ( input === output );
// returns true
```

</section>

<!-- /.usage -->

<section class="examples">

## Examples

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

```javascript
var identity = require( '@stdlib/utils-identity-function' );

var v = identity( 3.14 );
// returns 3.14

v = identity( true );
// returns true

v = identity( null );
// returns null

v = identity( void 0 );
// returns undefined

v = identity();
// returns undefined
```

</section>

<!-- /.examples -->

<!-- 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/utils-constant-function`][@stdlib/utils/constant-function]</span><span class="delimiter">: </span><span class="description">constant function.</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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[npm-url]: https://npmjs.org/package/@stdlib/utils-identity-function

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

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

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[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/utils-identity-function/tree/deno
[deno-readme]: https://github.com/stdlib-js/utils-identity-function/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/utils-identity-function/tree/umd
[umd-readme]: https://github.com/stdlib-js/utils-identity-function/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/utils-identity-function/tree/esm
[esm-readme]: https://github.com/stdlib-js/utils-identity-function/blob/esm/README.md
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[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/utils-identity-function/main/LICENSE

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[@stdlib/utils/constant-function]: https://www.npmjs.com/package/@stdlib/utils-constant-function

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</section>

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