has.js (1272B)
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 hasProp = require( './../../has-property' ); 24 25 26 // MAIN // 27 28 /** 29 * Returns a boolean indicating whether an object has a nested property. 30 * 31 * @private 32 * @param {*} v - value to test 33 * @param {Array} props - list of properties defining a key path 34 * @returns {boolean} boolean indicating whether an object has a nested property 35 */ 36 function deepHasProp( v, props ) { 37 var len = props.length; 38 var i; 39 if ( len === 0 ) { 40 return false; 41 } 42 for ( i = 0; i < len; i++ ) { 43 if ( hasProp( v, props[i] ) ) { 44 v = v[ props[ i ] ]; 45 } else { 46 return false; 47 } 48 } 49 return true; 50 } 51 52 53 // EXPORTS // 54 55 module.exports = deepHasProp;