arraylikefcn.js (2032B)
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 isArrayLike = require( './../../../is-array-like' ); 24 25 26 // MAIN // 27 28 /** 29 * Returns a function which tests if every element in an array-like object passes a test condition. 30 * 31 * @param {Function} predicate - function to apply 32 * @throws {TypeError} must provide a function 33 * @returns {Function} an array-like object function 34 * 35 * @example 36 * var isOdd = require( '@stdlib/assert/is-odd' ); 37 * 38 * var arr1 = [ 1, 3, 5, 7 ]; 39 * var arr2 = [ 3, 5, 8 ]; 40 * 41 * var validate = arraylikefcn( isOdd ); 42 * 43 * var bool = validate( arr1 ); 44 * // returns true 45 * 46 * bool = validate( arr2 ); 47 * // returns false 48 */ 49 function arraylikefcn( predicate ) { 50 if ( typeof predicate !== 'function' ) { 51 throw new TypeError( 'invalid argument. Must provide a function. Value: `' + predicate + '`.' ); 52 } 53 return every; 54 55 /** 56 * Tests if every element in an array-like object passes a test condition. 57 * 58 * @private 59 * @param {*} value - value to test 60 * @returns {boolean} boolean indicating whether a value is an array-like object for which all elements pass a test condition 61 */ 62 function every( value ) { 63 var len; 64 var i; 65 if ( !isArrayLike( value ) ) { 66 return false; 67 } 68 len = value.length; 69 if ( len === 0 ) { 70 return false; 71 } 72 for ( i = 0; i < len; i++ ) { 73 if ( predicate( value[ i ] ) === false ) { 74 return false; 75 } 76 } 77 return true; 78 } 79 } 80 81 82 // EXPORTS // 83 84 module.exports = arraylikefcn;