/** * @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 isCollection = require( '@stdlib/assert/is-collection' ); var isFunction = require( '@stdlib/assert/is-function' ); // MAIN // /** * Tests whether all elements in a collection pass a test implemented by a predicate function. * * @param {Collection} collection - input collection * @param {Function} predicate - test function * @param {*} [thisArg] - execution context * @throws {TypeError} first argument must be a collection * @throws {TypeError} second argument must be a function * @returns {boolean} boolean indicating whether all elements pass a test * * @example * function isPositive( v ) { * return ( v > 0 ); * } * * var arr = [ 1, 2, 3, 4 ]; * * var bool = everyBy( arr, isPositive ); * // returns true */ function everyBy( collection, predicate, thisArg ) { var out; var len; var i; if ( !isCollection( collection ) ) { throw new TypeError( 'invalid argument. First argument must be a collection. Value: `'+collection+'`.' ); } if ( !isFunction( predicate ) ) { throw new TypeError( 'invalid argument. Second argument must be a function. Value: `'+predicate+'`.' ); } len = collection.length; for ( i = 0; i < len; i++ ) { out = predicate.call( thisArg, collection[ i ], i, collection ); if ( !out ) { return false; } // Account for dynamically resizing a collection: len = collection.length; } return true; } // EXPORTS // module.exports = everyBy;