npm package: @stdlib/assert-is-lowercase
Description: Test if a value is a lowercase string.
Author: The Stdlib Authors
Latest version: 0.2.3

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<details>
  <summary>
    About stdlib...
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# isLowercase

[![NPM version][npm-image]][npm-url] [![Build Status][test-image]][test-url] [![Coverage Status][coverage-image]][coverage-url] <!-- [![dependencies][dependencies-image]][dependencies-url] -->

> Test if a value is a lowercase string.

<section class="installation">

## Installation

```bash
npm install @stdlib/assert-is-lowercase
```

</section>

<section class="usage">

## Usage

```javascript
var isLowercase = require( '@stdlib/assert-is-lowercase' );
```

#### isLowercase( value )

Tests if a `value` is a lowercase `string`.

```javascript
var bool = isLowercase( 'salt and light' );
// returns true

bool = isLowercase( 'HELLO' );
// returns false

bool = isLowercase( 'World' );
// returns false
```

</section>

<!-- /.usage -->

<section class="notes">

## Notes

-   This function validates that a `value` is a `string`. For all other types, the function returns `false`.

</section>

<!-- /.notes -->

<section class="examples">

## Examples

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

```javascript
var isLowercase = require( '@stdlib/assert-is-lowercase' );

var bool = isLowercase( 'hello' );
// returns true

bool = isLowercase( '' );
// returns false

bool = isLowercase( 'Hello' );
// returns false

bool = isLowercase( 'HELLO' );
// 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-lowercase-cli`][@stdlib/assert-is-lowercase-cli]</span><span class="delimiter">: </span><span class="description">CLI package for use as a command-line utility.</span>
-   <span class="package-name">[`@stdlib/assert-is-string`][@stdlib/assert/is-string]</span><span class="delimiter">: </span><span class="description">test if a value is a string.</span>
-   <span class="package-name">[`@stdlib/assert-is-uppercase`][@stdlib/assert/is-uppercase]</span><span class="delimiter">: </span><span class="description">test if a value is an uppercase string.</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="main-repo" >

* * *

## Notice

This package is part of [stdlib][stdlib], a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop [stdlib][stdlib], see the main project [repository][stdlib].

#### Community

[![Chat][chat-image]][chat-url]

---

## License

See [LICENSE][stdlib-license].


## Copyright

Copyright &copy; 2016-2026. The Stdlib [Authors][stdlib-authors].

</section>

<!-- /.stdlib -->

<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="links">

[@stdlib/assert-is-lowercase-cli]: https://www.npmjs.com/package/@stdlib/assert-is-lowercase-cli

[npm-image]: http://img.shields.io/npm/v/@stdlib/assert-is-lowercase.svg
[npm-url]: https://npmjs.org/package/@stdlib/assert-is-lowercase

[test-image]: https://github.com/stdlib-js/assert-is-lowercase/actions/workflows/test.yml/badge.svg?branch=v0.2.3
[test-url]: https://github.com/stdlib-js/assert-is-lowercase/actions/workflows/test.yml?query=branch:v0.2.3

[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/assert-is-lowercase/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/assert-is-lowercase?branch=main

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[stdlib]: https://github.com/stdlib-js/stdlib

[stdlib-authors]: https://github.com/stdlib-js/stdlib/graphs/contributors

[cli-section]: https://github.com/stdlib-js/assert-is-lowercase#cli
[cli-url]: https://github.com/stdlib-js/assert-is-lowercase/tree/cli
[@stdlib/assert-is-lowercase]: https://github.com/stdlib-js/assert-is-lowercase/tree/main

[umd]: https://github.com/umdjs/umd
[es-module]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules

[deno-url]: https://github.com/stdlib-js/assert-is-lowercase/tree/deno
[deno-readme]: https://github.com/stdlib-js/assert-is-lowercase/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/assert-is-lowercase/tree/umd
[umd-readme]: https://github.com/stdlib-js/assert-is-lowercase/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/assert-is-lowercase/tree/esm
[esm-readme]: https://github.com/stdlib-js/assert-is-lowercase/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/assert-is-lowercase/blob/main/branches.md

[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/assert-is-lowercase/main/LICENSE

[standard-streams]: https://en.wikipedia.org/wiki/Standard_streams

[mdn-regexp]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions

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

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

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

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

</section>

<!-- /.links -->