dset.js (1798B)
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 isObjectLike = require( '@stdlib/assert/is-object-like' ); 24 var hasOwnProp = require( '@stdlib/assert/has-own-property' ); 25 var isFunction = require( '@stdlib/assert/is-function' ); 26 27 28 // MAIN // 29 30 /** 31 * Sets a nested property. 32 * 33 * @private 34 * @param {ObjectLike} obj - input object 35 * @param {Array} props - list of properties defining a key path 36 * @param {boolean} create - boolean indicating whether to create a path if the key path does not already exist 37 * @param {*} val - value to set 38 * @returns {boolean} boolean indicating if the property was successfully set 39 */ 40 function deepSet( obj, props, create, val ) { 41 var bool; 42 var len; 43 var v; 44 var p; 45 var i; 46 47 len = props.length; 48 bool = false; 49 v = obj; 50 for ( i = 0; i < len; i++ ) { 51 p = props[ i ]; 52 if ( isObjectLike( v ) ) { 53 if ( !hasOwnProp( v, p ) ) { 54 if ( create ) { 55 v[ p ] = {}; 56 } else { 57 break; 58 } 59 } 60 if ( i === len-1 ) { 61 if ( isFunction( val ) ) { 62 v[ p ] = val( v[ p ] ); 63 } else { 64 v[ p ] = val; 65 } 66 bool = true; 67 } else { 68 v = v[ p ]; 69 } 70 } else { 71 break; 72 } 73 } 74 return bool; 75 } 76 77 78 // EXPORTS // 79 80 module.exports = deepSet;