npm package: @stdlib/object-assign-in
Description: Copy enumerable own and inherited properties from one or more source objects to a target object.
Author: The Stdlib Authors
Latest version: 0.1.1

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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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# assignIn

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

> Copy enumerable own and inherited properties from one or more source objects to a target object.

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<section class="intro">

</section>

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<!-- Package usage documentation. -->

<section class="installation">

## Installation

```bash
npm install @stdlib/object-assign-in
```

</section>

<section class="usage">

## Usage

```javascript
var assignIn = require( '@stdlib/object-assign-in' );
```

#### assignIn( target, source1\[, source2\[,...,sourceN]] )

Copies enumerable own and inherited properties from one or more source objects to a target object.

```javascript
function Foo() {
    this.a = 'beep';
    return this;
}

Foo.prototype.b = 'boop';

var x = {};
var y = new Foo();

var z = assignIn( x, y );
// returns { 'a': 'beep', 'b': 'boop' }

var bool = ( z === x );
// returns true
```

</section>

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

<section class="notes">

## Notes

-   If a property key is present in multiple sources, the property from the last source that defines the key prevails.
-   The target object is mutated.
-   Both string and symbol properties are copied.

</section>

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<!-- Package usage examples. -->

<section class="examples">

## Examples

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

```javascript
var assignIn = require( '@stdlib/object-assign-in' );

function Foo() {
    this.a = 1;
    return this;
}

Foo.prototype.b = 2;

function Bar() {
    this.c = 3;
    return this;
}

Bar.prototype.d = 4;

var obj1 = new Foo();
var obj2 = new Bar();

var result = assignIn( {}, obj1, obj2 );
// returns { 'a': 1, 'b': 2, 'c': 3, 'd': 4 }
```

</section>

<!-- /.examples -->

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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].

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[npm-url]: https://npmjs.org/package/@stdlib/object-assign-in

[test-image]: https://github.com/stdlib-js/object-assign-in/actions/workflows/test.yml/badge.svg?branch=v0.1.1
[test-url]: https://github.com/stdlib-js/object-assign-in/actions/workflows/test.yml?query=branch:v0.1.1

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

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

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

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