Test if an object has a specified property.
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> Test if an object has a specified property.
``bash`
npm install @stdlib/assert-has-own-property
`javascript`
var hasOwnProp = require( '@stdlib/assert-has-own-property' );
#### hasOwnProp( value, property )
Returns a boolean indicating if a value has a specified property.
`javascript
var value = {
'beep': 'boop'
};
var bool = hasOwnProp( value, 'beep' );
// returns true
bool = hasOwnProp( value, 'bap' );
// returns false
`
- In contrast to the native [Object.prototype.hasOwnProperty][mdn-object-has-own-property], this function does not throw when provided null or undefined. Instead, the function returns false.
`javascript
var bool = hasOwnProp( null, 'a' );
// returns false
bool = hasOwnProp( void 0, 'a' );
// returns false
`
- Value arguments other than null or undefined are coerced to objects.
`javascript`
var bool = hasOwnProp( 'beep', 'length' );
// returns true
- Property arguments are coerced to strings.
`javascript
var value = {
'null': false
};
var bool = hasOwnProp( value, null );
// returns true
value = {
'[object Object]': false
};
bool = hasOwnProp( value, {} );
// returns true
`
`javascript
var hasOwnProp = require( '@stdlib/assert-has-own-property' );
var bool = hasOwnProp( { 'a': 'b' }, 'a' );
// returns true
bool = hasOwnProp( { 'a': 'b' }, 'c' );
// returns false
bool = hasOwnProp( { 'a': 'b' }, null );
// returns false
bool = hasOwnProp( {}, 'hasOwnProp' );
// returns false
bool = hasOwnProp( null, 'a' );
// returns false
bool = hasOwnProp( void 0, 'a' );
// returns false
bool = hasOwnProp( { 'null': false }, null );
// returns true
bool = hasOwnProp( { '[object Object]': false }, {} );
// returns true
`
*
- [@stdlib/assert-has-property][@stdlib/assert/has-property]: test if an object has a specified property, either own or inherited.
*
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].
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---
See [LICENSE][stdlib-license].
Copyright © 2016-2026. The Stdlib [Authors][stdlib-authors].
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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/assert-has-own-property/tree/deno
[deno-readme]: https://github.com/stdlib-js/assert-has-own-property/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/assert-has-own-property/tree/umd
[umd-readme]: https://github.com/stdlib-js/assert-has-own-property/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/assert-has-own-property/tree/esm
[esm-readme]: https://github.com/stdlib-js/assert-has-own-property/blob/esm/README.md
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[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/assert-has-own-property/main/LICENSE
[mdn-object-has-own-property]: https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Object/hasOwnProperty
[@stdlib/assert/has-property]: https://www.npmjs.com/package/@stdlib/assert-has-property