npm package: @stdlib/assert-is-nonconfigurable-property
Description: Test if an object's own property is non-configurable.
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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# isNonConfigurableProperty

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

> Test if an object's own property is non-configurable.

<section class="installation">

## Installation

```bash
npm install @stdlib/assert-is-nonconfigurable-property
```

</section>

<section class="usage">

## Usage

```javascript
var isNonConfigurableProperty = require( '@stdlib/assert-is-nonconfigurable-property' );
```

#### isNonConfigurableProperty( value, property )

Returns a `boolean` indicating if a `value` has a non-configurable `property` (i.e., a property which cannot be deleted and whose descriptor cannot be changed).

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

var obj = {
    'foo': 'bar'
};

defineProperty( obj, 'beep', {
    'configurable': false,
    'enumerable': true,
    'writable': true,
    'value': 'boop'
});

var bool = isNonConfigurableProperty( obj, 'beep' );
// returns true

bool = isNonConfigurableProperty( obj, 'foo' );
// returns false
```

</section>

<!-- /.usage -->

<section class="notes">

## Notes

-   Value arguments other than `null` or `undefined` are coerced to `objects`.

    ```javascript
    var bool = isNonConfigurableProperty( 'beep', 'length' );
    // returns true
    ```

</section>

<!-- /.notes -->

<section class="examples">

## Examples

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

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

```javascript
var isNonConfigurableProperty = require( '@stdlib/assert-is-nonconfigurable-property' );

var bool = isNonConfigurableProperty( [ 'a' ], 'length' );
// returns true

bool = isNonConfigurableProperty( { 'a': 'b' }, 'a' );
// returns false

bool = isNonConfigurableProperty( [ 'a' ], 0 );
// returns false

bool = isNonConfigurableProperty( {}, 'toString' );
// returns false

bool = isNonConfigurableProperty( {}, 'hasOwnProperty' );
// returns false

bool = isNonConfigurableProperty( null, 'a' );
// returns false

bool = isNonConfigurableProperty( void 0, 'a' );
// returns false

bool = isNonConfigurableProperty( { 'null': false }, null );
// returns false

bool = isNonConfigurableProperty( { '[object Object]': false }, {} );
// 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-configurable-property`][@stdlib/assert/is-configurable-property]</span><span class="delimiter">: </span><span class="description">test if an object's own property is configurable.</span>
-   <span class="package-name">[`@stdlib/assert-is-enumerable-property`][@stdlib/assert/is-enumerable-property]</span><span class="delimiter">: </span><span class="description">test if an object's own property is enumerable.</span>
-   <span class="package-name">[`@stdlib/assert-is-nonconfigurable-property-in`][@stdlib/assert/is-nonconfigurable-property-in]</span><span class="delimiter">: </span><span class="description">test if an object's own or inherited property is non-configurable.</span>
-   <span class="package-name">[`@stdlib/assert-is-nonenumerable-property`][@stdlib/assert/is-nonenumerable-property]</span><span class="delimiter">: </span><span class="description">test if an object's own property is non-enumerable.</span>
-   <span class="package-name">[`@stdlib/assert-is-readable-property`][@stdlib/assert/is-readable-property]</span><span class="delimiter">: </span><span class="description">test if an object's own property is readable.</span>
-   <span class="package-name">[`@stdlib/assert-is-writable-property`][@stdlib/assert/is-writable-property]</span><span class="delimiter">: </span><span class="description">test if an object's own property is writable.</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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<!-- <related-links> -->

[@stdlib/assert/is-configurable-property]: https://www.npmjs.com/package/@stdlib/assert-is-configurable-property

[@stdlib/assert/is-enumerable-property]: https://www.npmjs.com/package/@stdlib/assert-is-enumerable-property

[@stdlib/assert/is-nonconfigurable-property-in]: https://www.npmjs.com/package/@stdlib/assert-is-nonconfigurable-property-in

[@stdlib/assert/is-nonenumerable-property]: https://www.npmjs.com/package/@stdlib/assert-is-nonenumerable-property

[@stdlib/assert/is-readable-property]: https://www.npmjs.com/package/@stdlib/assert-is-readable-property

[@stdlib/assert/is-writable-property]: https://www.npmjs.com/package/@stdlib/assert-is-writable-property

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</section>

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