Return the prototype of a provided object.
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> Return the prototype of a provided object.
``bash`
npm install @stdlib/utils-get-prototype-of
`javascript`
var getPrototypeOf = require( '@stdlib/utils-get-prototype-of' );
#### getPrototypeOf( value )
Returns the prototype of an input value.
`javascript`
var proto = getPrototypeOf( {} );
// returns {}
- In contrast to the native [Object.getPrototypeOf][object-get-prototype-of], this function does not throw when provided null or undefined. Instead, similar to when provided any value with no inherited properties, the function returns null.
`javascript
var proto = getPrototypeOf( Object.create( null ) );
// returns null
proto = getPrototypeOf( null );
// returns null
proto = getPrototypeOf( void 0 );
// returns null
`
- Value arguments other than null or undefined are coerced to objects.
`javascript
var proto = getPrototypeOf( 'beep' );
// returns String.prototype
proto = getPrototypeOf( 5 );
// returns Number.prototype
`
This behavior matches ES6/ES2015 native [Object.getPrototypeOf][object-get-prototype-of] behavior. In ES5, the native [Object.getPrototypeOf][object-get-prototype-of] throws when provided non-object values.
`javascript
var getPrototypeOf = require( '@stdlib/utils-get-prototype-of' );
var proto = getPrototypeOf( 'beep' );
// returns String.prototype
proto = getPrototypeOf( 5 );
// returns Number.prototype
proto = getPrototypeOf( true );
// returns Boolean.prototype
proto = getPrototypeOf( null );
// returns null
proto = getPrototypeOf( void 0 );
// returns null
proto = getPrototypeOf( [] );
// returns Array.prototype
proto = getPrototypeOf( {} );
// returns {}
proto = getPrototypeOf( function foo() {} );
// returns Function.prototype
`
*
- [@stdlib/assert-is-prototype-of][@stdlib/assert/is-prototype-of]: test if an object's prototype chain contains a provided prototype.
*
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].
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[es-module]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules
[deno-url]: https://github.com/stdlib-js/utils-get-prototype-of/tree/deno
[deno-readme]: https://github.com/stdlib-js/utils-get-prototype-of/blob/deno/README.md
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[object-get-prototype-of]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/getPrototypeOf
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