main.js (1472B)
1 /** 2 * @license Apache-2.0 3 * 4 * Copyright (c) 2018 The Stdlib Authors. 5 * 6 * Licensed under the Apache License, Version 2.0 (the "License"); 7 * you may not use this file except in compliance with the License. 8 * You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, software 13 * distributed under the License is distributed on an "AS IS" BASIS, 14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15 * See the License for the specific language governing permissions and 16 * limitations under the License. 17 */ 18 19 'use strict'; 20 21 // MODULES // 22 23 var isString = require( './../../is-string' ).isPrimitive; 24 var reWhitespace = require( '@stdlib/regexp/whitespace' ); 25 26 27 // VARIABLES // 28 29 var RE = new RegExp( '^'+reWhitespace.REGEXP.source+'+$' ); 30 31 32 // MAIN // 33 34 /** 35 * Tests whether a string contains only white space characters. 36 * 37 * @param {*} x - value to test 38 * @returns {boolean} boolean indicating if a string contains only white space characters 39 * 40 * @example 41 * var out = isWhitespace( ' ' ); 42 * // returns true 43 * 44 * @example 45 * var out = isWhitespace( 'beep boop' ); 46 * // returns false 47 * 48 * @example 49 * var out = isWhitespace( '' ); 50 * // returns false 51 * 52 * @example 53 * var out = isWhitespace( 123 ); 54 * // returns false 55 */ 56 function isWhitespace( x ) { 57 if ( !isString( x ) ) { 58 return false; 59 } 60 return RE.test( x ); 61 } 62 63 64 // EXPORTS // 65 66 module.exports = isWhitespace;