time-to-botec/squiggle/node_modules/@stdlib/assert/is-undefined-or-null/README.md

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# isUndefinedOrNull

> Test if a value is undefined or null.

<section class="usage">

## Usage

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

#### isUndefinedOrNull( value )

Tests if a `value` is `undefined` or `null`.

<!-- eslint-disable no-undefined -->

```javascript
var bool = isUndefinedOrNull( undefined );
// returns true

bool = isUndefinedOrNull( null );
// returns true
```

</section>

<!-- /.usage -->

<section class="examples">

## Examples

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

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

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

var bool;
var x;

bool = isUndefinedOrNull( x );
// returns true

bool = isUndefinedOrNull( undefined );
// returns true

bool = isUndefinedOrNull( void 0 );
// returns true

bool = isUndefinedOrNull( null );
// returns true

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

bool = isUndefinedOrNull( 5 );
// returns false

bool = isUndefinedOrNull( true );
// returns false

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

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

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

</section>

<!-- /.examples -->

<section class="links">

</section>

<!-- /.links -->