Test if a value is an uppercase string.
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> Test if a value is an uppercase string.
``bash`
npm install @stdlib/assert-is-uppercase
`javascript`
var isUppercase = require( '@stdlib/assert-is-uppercase' );
#### isUppercase( value )
Tests if a value is an uppercase string.
`javascript
var bool = isUppercase( 'HELLO' );
// returns true
bool = isUppercase( 'salt and light' );
// returns false
`
- The function validates that a value is a string. For all other types, the function returns false.
`javascript
var isUppercase = require( '@stdlib/assert-is-uppercase' );
var bool = isUppercase( 'HELLO' );
// returns true
bool = isUppercase( '' );
// returns false
bool = isUppercase( 'Hello' );
// returns false
bool = isUppercase( 'hello' );
// returns false
`
- [@stdlib/assert-is-uppercase-cli][@stdlib/assert-is-uppercase-cli]: CLI package for use as a command-line utility.
- [@stdlib/assert-is-lowercase][@stdlib/assert/is-lowercase]: test if a value is a lowercase string.
- [@stdlib/assert-is-string][@stdlib/assert/is-string]: test if a value is a string.
*
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].
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---
See [LICENSE][stdlib-license].
Copyright © 2016-2026. The Stdlib [Authors][stdlib-authors].
[@stdlib/assert-is-uppercase-cli]: https://www.npmjs.com/package/@stdlib/assert-is-uppercase-cli
[npm-image]: http://img.shields.io/npm/v/@stdlib/assert-is-uppercase.svg
[npm-url]: https://npmjs.org/package/@stdlib/assert-is-uppercase
[test-image]: https://github.com/stdlib-js/assert-is-uppercase/actions/workflows/test.yml/badge.svg?branch=v0.2.3
[test-url]: https://github.com/stdlib-js/assert-is-uppercase/actions/workflows/test.yml?query=branch:v0.2.3
[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/assert-is-uppercase/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/assert-is-uppercase?branch=main
[chat-image]: https://img.shields.io/badge/zulip-join_chat-brightgreen.svg
[chat-url]: https://stdlib.zulipchat.com
[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-uppercase#cli
[cli-url]: https://github.com/stdlib-js/assert-is-uppercase/tree/cli
[@stdlib/assert-is-uppercase]: https://github.com/stdlib-js/assert-is-uppercase/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-uppercase/tree/deno
[deno-readme]: https://github.com/stdlib-js/assert-is-uppercase/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/assert-is-uppercase/tree/umd
[umd-readme]: https://github.com/stdlib-js/assert-is-uppercase/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/assert-is-uppercase/tree/esm
[esm-readme]: https://github.com/stdlib-js/assert-is-uppercase/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/assert-is-uppercase/blob/main/branches.md
[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/assert-is-uppercase/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
[@stdlib/assert/is-lowercase]: https://www.npmjs.com/package/@stdlib/assert-is-lowercase
[@stdlib/assert/is-string]: https://www.npmjs.com/package/@stdlib/assert-is-string