npm package: @stdlib/utils-define-read-only-property
Description: Define a read-only property.
Author: The Stdlib Authors
Latest version: 0.2.3

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<details>
  <summary>
    About stdlib...
  </summary>
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</details>

# Read-Only

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

> [Define][@stdlib/utils/define-property] a **read-only** property.

<section class="installation">

## Installation

```bash
npm install @stdlib/utils-define-read-only-property
```

</section>

<section class="usage">

## Usage

```javascript
var setReadOnly = require( '@stdlib/utils-define-read-only-property' );
```

#### setReadOnly( obj, prop, value )

[Defines][@stdlib/utils/define-property] a **read-only** property.

<!-- run throws: true -->

```javascript
var obj = {};

setReadOnly( obj, 'foo', 'bar' );

obj.foo = 'boop';
// throws <Error>
```

</section>

<!-- /.usage -->

<section class="notes">

## Notes

-   Read-only properties are **enumerable** and **non-configurable**.

</section>

<!-- /.notes -->

<section class="examples">

## Examples

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

```javascript
var setReadOnly = require( '@stdlib/utils-define-read-only-property' );

function Foo( name ) {
    if ( !(this instanceof Foo) ) {
        return new Foo( name );
    }
    setReadOnly( this, 'name', name );
    return this;
}

var foo = new Foo( 'beep' );

try {
    foo.name = 'boop';
} catch ( err ) {
    console.error( err.message );
}
```

</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-define-read-only-accessor`][@stdlib/utils/define-read-only-accessor]</span><span class="delimiter">: </span><span class="description">define a read-only accessor.</span>
-   <span class="package-name">[`@stdlib/utils-define-read-write-accessor`][@stdlib/utils/define-read-write-accessor]</span><span class="delimiter">: </span><span class="description">define a read-write accessor.</span>
-   <span class="package-name">[`@stdlib/utils-define-write-only-accessor`][@stdlib/utils/define-write-only-accessor]</span><span class="delimiter">: </span><span class="description">define a write-only accessor.</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>

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[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/utils-define-read-only-property/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/utils-define-read-only-property?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/utils-define-read-only-property/tree/deno
[deno-readme]: https://github.com/stdlib-js/utils-define-read-only-property/blob/deno/README.md
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[esm-url]: https://github.com/stdlib-js/utils-define-read-only-property/tree/esm
[esm-readme]: https://github.com/stdlib-js/utils-define-read-only-property/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/utils-define-read-only-property/blob/main/branches.md

[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/utils-define-read-only-property/main/LICENSE

[@stdlib/utils/define-property]: https://www.npmjs.com/package/@stdlib/utils-define-property

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

[@stdlib/utils/define-read-only-accessor]: https://www.npmjs.com/package/@stdlib/utils-define-read-only-accessor

[@stdlib/utils/define-read-write-accessor]: https://www.npmjs.com/package/@stdlib/utils-define-read-write-accessor

[@stdlib/utils/define-write-only-accessor]: https://www.npmjs.com/package/@stdlib/utils-define-write-only-accessor

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

</section>

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