time-to-botec

Benchmark sampling in different programming languages
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map_values.js (1983B)

      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 isFunction = require( '@stdlib/assert/is-function' );
     24 var hasOwnProp = require( '@stdlib/assert/has-own-property' );
     25 
     26 
     27 // MAIN //
     28 
     29 /**
     30 * Maps values from one object to a new object having the same keys.
     31 *
     32 * ## Notes
     33 *
     34 * -   Iteration order is **not** guaranteed.
     35 * -   The function only operates on own properties, not inherited properties.
     36 *
     37 *
     38 * @param {Object} obj - source object
     39 * @param {Function} transform - transform function
     40 * @throws {TypeError} first argument must be an object
     41 * @throws {TypeError} second argument must be a function
     42 * @returns {Object} new object
     43 *
     44 * @example
     45 * function transform( value, key ) {
     46 *     return key + value;
     47 * }
     48 *
     49 * var obj1 = {
     50 *     'a': 1,
     51 *     'b': 2
     52 * };
     53 *
     54 * var obj2 = mapValues( obj1, transform );
     55 * // returns { 'a': 'a1', 'b': 'b2' }
     56 */
     57 function mapValues( obj, transform ) {
     58 	var out;
     59 	var key;
     60 	if ( typeof obj !== 'object' || obj === null ) {
     61 		throw new TypeError( 'invalid argument. First argument must be an object. Value: `'+obj+'`.' );
     62 	}
     63 	if ( !isFunction( transform ) ) {
     64 		throw new TypeError( 'invalid argument. Second argument must be a function. Value: `'+transform+'`.' );
     65 	}
     66 	out = {};
     67 	for ( key in obj ) {
     68 		if ( hasOwnProp( obj, key ) ) {
     69 			out[ key ] = transform( obj[ key ], key, obj );
     70 		}
     71 	}
     72 	return out;
     73 }
     74 
     75 
     76 // EXPORTS //
     77 
     78 module.exports = mapValues;