@stdlib/utils/get-prototype-of/README.md

Standard utilities.

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# getPrototypeOf

> Return the prototype of a provided object.

<section class="usage">

## Usage

```javascript
var getPrototypeOf = require( '@stdlib/utils/get-prototype-of' );
```

#### getPrototypeOf( value )

Returns the `prototype` of an input `value`.

```javascript
var proto = getPrototypeOf( {} );
// returns {}
```

</section>

<!-- /.usage -->

<section class="notes">

## Notes

-   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.

</section>

<!-- /.notes -->

<section class="examples">

## Examples

<!-- eslint-disable no-restricted-syntax, no-empty-function -->

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

```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
```

</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-prototype-of`][@stdlib/assert/is-prototype-of]</span><span class="delimiter">: </span><span class="description">test if an object's prototype chain contains a provided prototype.</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="links">

[object-get-prototype-of]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/getPrototypeOf

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

[@stdlib/assert/is-prototype-of]: https://www.npmjs.com/package/@stdlib/assert-is-prototype-of

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

</section>

<!-- /.links -->