@stdlib/assert/is-null/README.md

Standard assertion utilities.

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# isNull

> Test if a value is null.

<section class="usage">

## Usage

```javascript
var isNull = require( '@stdlib/assert/is-null' );
```

#### isNull( value )

Tests if a `value` is `null`.

```javascript
var bool = isNull( null );
// returns true
```

</section>

<!-- /.usage -->

<section class="examples">

## Examples

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

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

```javascript
var isNull = require( '@stdlib/assert/is-null' );

var bool = isNull( null );
// returns true

bool = isNull( 'beep' );
// returns false

bool = isNull( 5 );
// returns false

bool = isNull( void 0 );
// returns false

bool = isNull( true );
// returns false

bool = isNull( {} );
// returns false

bool = isNull( [] );
// returns false

bool = isNull( function foo() {} );
// returns false
```

</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-undefined`][@stdlib/assert/is-undefined]</span><span class="delimiter">: </span><span class="description">test if a value is undefined.</span>
-   <span class="package-name">[`@stdlib/assert/is-undefined-or-null`][@stdlib/assert/is-undefined-or-null]</span><span class="delimiter">: </span><span class="description">test if a value is undefined or null.</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">

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

[@stdlib/assert/is-undefined]: https://github.com/stdlib-js/assert/tree/main/is-undefined

[@stdlib/assert/is-undefined-or-null]: https://github.com/stdlib-js/assert/tree/main/is-undefined-or-null

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

</section>

<!-- /.links -->