npm package: @stdlib/assert-deep-equal
Description: Test for deep equality between two values.
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>

# deepEqual

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

> Test for deep equality between two values.

<section class="installation">

## Installation

```bash
npm install @stdlib/assert-deep-equal
```

</section>

<section class="usage">

## Usage

```javascript
var deepEqual = require( '@stdlib/assert-deep-equal' );
```

#### deepEqual( a, b )

Returns a `boolean` indicating if `a` is deep equal to `b`.

<!-- eslint-disable object-curly-newline, object-curly-spacing -->

```javascript
var bool = deepEqual( [ 1, 2, 3 ], [ 1, 2, 3 ] );
// returns true

bool = deepEqual( [ 1, 2, 3 ], [ 1, 2, '3' ] );
// returns false

bool = deepEqual( { 'a': 2 }, { 'a': [ 2 ] } );
// returns false
```

</section>

<!-- /.usage -->

<section class="notes">

## Notes

-   The function uses strict equality checks (`===`) and does not perform any type coercion.
-   When given two objects, only enumerable own properties are recursively compared.

</section>

<!-- /.notes -->

<section class="examples">

## Examples

<!-- eslint no-undef: "error", object-curly-newline: "off", object-curly-spacing: "off" -->

```javascript
var deepEqual = require( '@stdlib/assert-deep-equal' );

var a = [ true, false, true ];
var b = [ true, false, true ];
var bool = deepEqual( a, b );
// returns true

b.pop();
bool = deepEqual( a, b );
// returns false

a = { 'a': { 'b': { 'c': 'd' } } };
b = { 'a': { 'b': { 'c': 'd' } } };
bool = deepEqual( a, b );
// returns true

b.a.b.c = null;
bool = deepEqual( a, b );
// returns false

a = { 'a': [ { 'b': 0 }, { 'c': 1 } ] };
b = { 'a': [ { 'b': 0 }, { 'c': 1 } ] };
bool = deepEqual( a, b );
// returns true

b = { 'a': [ { 'b': [ 0 ] }, { 'c': '1' } ] };
bool = deepEqual( a, b );
// returns false
```

</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/assert-is-strict-equal`][@stdlib/assert/is-strict-equal]</span><span class="delimiter">: </span><span class="description">test if two arguments are strictly equal.</span>
-   <span class="package-name">[`@stdlib/assert-is-same-value`][@stdlib/assert/is-same-value]</span><span class="delimiter">: </span><span class="description">test if two arguments are the same value.</span>

</section>

<!-- /.related -->

<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->


<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/assert-deep-equal.svg
[npm-url]: https://npmjs.org/package/@stdlib/assert-deep-equal

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

[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/assert-deep-equal/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/assert-deep-equal?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/assert-deep-equal/tree/deno
[deno-readme]: https://github.com/stdlib-js/assert-deep-equal/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/assert-deep-equal/tree/umd
[umd-readme]: https://github.com/stdlib-js/assert-deep-equal/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/assert-deep-equal/tree/esm
[esm-readme]: https://github.com/stdlib-js/assert-deep-equal/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/assert-deep-equal/blob/main/branches.md

[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/assert-deep-equal/main/LICENSE

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

[@stdlib/assert/is-strict-equal]: https://www.npmjs.com/package/@stdlib/assert-is-strict-equal

[@stdlib/assert/is-same-value]: https://www.npmjs.com/package/@stdlib/assert-is-same-value

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

</section>

<!-- /.links -->