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

Standard assertion utilities.

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# isFalsy

> Test if a value is falsy.

<section class="usage">

## Usage

```javascript
var isFalsy = require( '@stdlib/assert/is-falsy' );
```

#### isFalsy( value )

Tests if a `value` is a value which translates to `false` when evaluated in a boolean context.

```javascript
var bool = isFalsy( false );
// returns true

bool = isFalsy( '' );
// returns true

bool = isFalsy( 0 );
// returns true

bool = isFalsy( NaN );
// returns true

bool = isFalsy( null );
// returns true

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

bool = isFalsy( [] );
// returns false
```

</section>

<!-- /.usage -->

<section class="examples">

## Examples

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

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

```javascript
var isFalsy = require( '@stdlib/assert/is-falsy' );

var bool = isFalsy( false );
// returns true

bool = isFalsy( 0 );
// returns true

bool = isFalsy( NaN );
// returns true

bool = isFalsy( '' );
// returns true

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

bool = isFalsy( null );
// returns true

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

bool = isFalsy( 5 );
// returns false

bool = isFalsy( true );
// returns false

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

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

bool = isFalsy( 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-falsy-array`][@stdlib/assert/is-falsy-array]</span><span class="delimiter">: </span><span class="description">test if a value is an array-like object containing only falsy values.</span>
-   <span class="package-name">[`@stdlib/assert/is-truthy`][@stdlib/assert/is-truthy]</span><span class="delimiter">: </span><span class="description">test if a value is truthy.</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-falsy-array]: https://github.com/stdlib-js/assert/tree/main/is-falsy-array

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

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

</section>

<!-- /.links -->