time-to-botec/squiggle/node_modules/@stdlib/assert/is-lowercase/lib/main.js

64 lines
1.4 KiB
JavaScript
Raw Normal View History

/**
* @license Apache-2.0
*
* Copyright (c) 2018 The Stdlib Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
'use strict';
// MODULES //
var lowercase = require( '@stdlib/string/lowercase' );
var uppercase = require( '@stdlib/string/uppercase' );
var isString = require( './../../is-string' ).isPrimitive;
// MAIN //
/**
* Tests if a value is a lowercase string.
*
* @param {*} value - value to test
* @returns {boolean} boolean indicating whether value is a lowercase string
*
* @example
* var bool = isLowercase( 'salt and light' );
* // returns true
*
* @example
* var bool = isLowercase( 'HELLO' );
* // returns false
*
* @example
* var bool = isLowercase( 'World' );
* // returns false
*
* @example
* var bool = isLowercase( '!' );
* // returns false
*/
function isLowercase( value ) {
return (
isString( value ) &&
value === lowercase( value ) &&
value !== uppercase( value )
);
}
// EXPORTS //
module.exports = isLowercase;