/** * @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( './../../is-collection' ); var isInteger = require( './../../is-integer' ).isPrimitive; var isString = require( './../../is-string' ).isPrimitive; var isnan = require( './../../is-nan' ).isPrimitive; // MAIN // /** * Tests if an array-like value contains a search value. * * @param {(Collection|string)} val - input value * @param {*} searchValue - search value * @param {integer} [position=0] - position at which to start searching for `searchValue` * @throws {TypeError} first argument must be array-like * @throws {Error} must provide a search value * @throws {TypeError} second argument must be a primitive string primitive when the first argument is a string * @throws {TypeError} third argument must be an integer * @returns {boolean} boolean indicating whether one value contains another * * @example * var bool = contains( 'last man standing', 'stand' ); * // returns true * * @example * var bool = contains( [ 1, 2, 3, 4 ], 2 ); * // returns true * * @example * var bool = contains( 'presidential election', 'president' ); * // returns true * * @example * var bool = contains( [ NaN, 2, 3, 4 ], NaN ); * // returns true * * @example * var bool = contains( 'javaScript', 'js' ); * // returns false * * @example * var bool = contains( [ 1, 2, 3, {} ], {} ); * // returns false * * @example * var bool = contains( 'Hidden Treasures', '' ); * // returns true */ function contains( val, searchValue, position ) { var len; var pos; var i; if ( !isCollection( val ) && !isString( val ) ) { throw new TypeError( 'invalid argument. First argument must be array-like. Value: `' + val + '`.' ); } if ( arguments.length < 2 ) { throw new Error( 'insufficient input arguments. Must provide a search value.' ); } if ( arguments.length > 2 ) { if ( !isInteger( position ) ) { throw new TypeError( 'invalid argument. Third argument must be an integer. Value: `' + position + '`.' ); } pos = position; if ( pos < 0 ) { pos = 0; } } else { pos = 0; } if ( isString( val ) ) { if ( !isString( searchValue ) ) { throw new TypeError( 'invalid argument. Second argument must be a string primitive. Value: `' + searchValue + '`.' ); } return val.indexOf( searchValue, pos ) !== -1; } len = val.length; if ( isnan( searchValue ) ) { for ( i = pos; i < len; i++ ) { if ( isnan( val[ i ] ) ) { return true; } } return false; } for ( i = pos; i < len; i++ ) { if ( val[ i ] === searchValue ) { return true; } } return false; } // EXPORTS // module.exports = contains;