main.js (1413B)
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 25 26 // MAIN // 27 28 /** 29 * Tests if a value is a binary string. 30 * 31 * @param {*} str - value to test 32 * @returns {boolean} boolean indicating if an input value is a binary string 33 * 34 * @example 35 * var bool = isBinaryString( '1000101' ); 36 * // returns true 37 * 38 * @example 39 * var bool = isBinaryString( 'beep' ); 40 * // returns false 41 * 42 * @example 43 * var bool = isBinaryString( '' ); 44 * // returns false 45 */ 46 function isBinaryString( str ) { 47 var ch; 48 var i; 49 if ( !isString( str ) ) { 50 return false; 51 } 52 if ( str.length === 0 ) { 53 return false; 54 } 55 for ( i = 0; i < str.length; i++ ) { 56 ch = str[ i ]; 57 if ( ch !== '1' && ch !== '0' ) { 58 return false; 59 } 60 } 61 return true; 62 } 63 64 65 // EXPORTS // 66 67 module.exports = isBinaryString;