bifocal/node_modules/@stdlib/assert-is-enumerable-property/README.md

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# isEnumerableProperty
[![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 enumerable.
<section class="installation">
## Installation
```bash
npm install @stdlib/assert-is-enumerable-property
```
</section>
<section class="usage">
## Usage
```javascript
var isEnumerableProperty = require( '@stdlib/assert-is-enumerable-property' );
```
#### isEnumerableProperty( value, property )
Returns a `boolean` indicating if a `value` has an enumerable `property`.
```javascript
var value = {
'beep': 'boop'
};
var bool = isEnumerableProperty( value, 'beep' );
// returns true
bool = isEnumerableProperty( value, 'constructor' );
// returns false
```
</section>
<!-- /.usage -->
<section class="notes">
## Notes
- In contrast to the native [Object.prototype.propertyIsEnumerable][mdn-object-property-is-enumerable], this function does **not** throw when provided `null` or `undefined`. Instead, the function returns `false`.
```javascript
var bool = isEnumerableProperty( null, 'a' );
// returns false
bool = isEnumerableProperty( void 0, 'a' );
// returns false
```
- Value arguments other than `null` or `undefined` are coerced to `objects`.
```javascript
var bool = isEnumerableProperty( 'beep', '1' );
// returns true
```
- Property arguments are coerced to `strings`.
```javascript
var value = {
'null': false
};
var bool = isEnumerableProperty( value, null );
// returns true
value = {
'[object Object]': false
};
bool = isEnumerableProperty( value, {} );
// returns true
```
</section>
<!-- /.notes -->
<section class="examples">
## Examples
<!-- eslint-disable object-curly-newline -->
<!-- eslint no-undef: "error" -->
```javascript
var isEnumerableProperty = require( '@stdlib/assert-is-enumerable-property' );
var bool = isEnumerableProperty( { 'a': 'b' }, 'a' );
// returns true
bool = isEnumerableProperty( [ 'a' ], 0 );
// returns true
bool = isEnumerableProperty( [ 'a' ], 'length' );
// returns false
bool = isEnumerableProperty( {}, 'toString' );
// returns false
bool = isEnumerableProperty( {}, 'hasOwnProperty' );
// returns false
bool = isEnumerableProperty( null, 'a' );
// returns false
bool = isEnumerableProperty( void 0, 'a' );
// returns false
bool = isEnumerableProperty( { 'null': false }, null );
// returns true
bool = isEnumerableProperty( { '[object Object]': false }, {} );
// returns true
```
</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-in`][@stdlib/assert/is-enumerable-property-in]</span><span class="delimiter">: </span><span class="description">test if an object's own or inherited property is enumerable.</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 -->
<!-- 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; 2016-2022. The Stdlib [Authors][stdlib-authors].
</section>
<!-- /.stdlib -->
<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
<section class="links">
[npm-image]: http://img.shields.io/npm/v/@stdlib/assert-is-enumerable-property.svg
[npm-url]: https://npmjs.org/package/@stdlib/assert-is-enumerable-property
[test-image]: https://github.com/stdlib-js/assert-is-enumerable-property/actions/workflows/test.yml/badge.svg
[test-url]: https://github.com/stdlib-js/assert-is-enumerable-property/actions/workflows/test.yml
[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/assert-is-enumerable-property/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/assert-is-enumerable-property?branch=main
<!--
[dependencies-image]: https://img.shields.io/david/stdlib-js/assert-is-enumerable-property.svg
[dependencies-url]: https://david-dm.org/stdlib-js/assert-is-enumerable-property/main
-->
[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-is-enumerable-property/tree/deno
[umd-url]: https://github.com/stdlib-js/assert-is-enumerable-property/tree/umd
[esm-url]: https://github.com/stdlib-js/assert-is-enumerable-property/tree/esm
[chat-image]: https://img.shields.io/gitter/room/stdlib-js/stdlib.svg
[chat-url]: https://gitter.im/stdlib-js/stdlib/
[stdlib]: https://github.com/stdlib-js/stdlib
[stdlib-authors]: https://github.com/stdlib-js/stdlib/graphs/contributors
[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/assert-is-enumerable-property/main/LICENSE
[mdn-object-property-is-enumerable]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/propertyIsEnumerable
<!-- <related-links> -->
[@stdlib/assert/is-configurable-property]: https://www.npmjs.com/package/@stdlib/assert-is-configurable-property
[@stdlib/assert/is-enumerable-property-in]: https://www.npmjs.com/package/@stdlib/assert-is-enumerable-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
<!-- </related-links> -->
</section>
<!-- /.links -->