time-to-botec/squiggle/node_modules/@stdlib/assert/has-own-property/README.md

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# hasOwnProperty

> Test if an object has a specified property.

<section class="usage">

## Usage

```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
```

</section>

<!-- /.usage -->

<section class="notes">

## Notes

-   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
    ```

</section>

<!-- /.notes -->

<section class="examples">

## Examples

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

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

```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( {}, 'hasOwnProperty' );
// 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
```

</section>

<!-- /.examples -->

<section class="links">

[mdn-object-has-own-property]: https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Object/hasOwnProperty

</section>

<!-- /.links -->