79 lines
1.9 KiB
JavaScript
79 lines
1.9 KiB
JavaScript
/**
|
|
* @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 isFunction = require( '@stdlib/assert/is-function' );
|
|
var hasOwnProp = require( '@stdlib/assert/has-own-property' );
|
|
|
|
|
|
// MAIN //
|
|
|
|
/**
|
|
* Maps values from one object to a new object having the same keys.
|
|
*
|
|
* ## Notes
|
|
*
|
|
* - Iteration order is **not** guaranteed.
|
|
* - The function only operates on own properties, not inherited properties.
|
|
*
|
|
*
|
|
* @param {Object} obj - source object
|
|
* @param {Function} transform - transform function
|
|
* @throws {TypeError} first argument must be an object
|
|
* @throws {TypeError} second argument must be a function
|
|
* @returns {Object} new object
|
|
*
|
|
* @example
|
|
* function transform( value, key ) {
|
|
* return key + value;
|
|
* }
|
|
*
|
|
* var obj1 = {
|
|
* 'a': 1,
|
|
* 'b': 2
|
|
* };
|
|
*
|
|
* var obj2 = mapValues( obj1, transform );
|
|
* // returns { 'a': 'a1', 'b': 'b2' }
|
|
*/
|
|
function mapValues( obj, transform ) {
|
|
var out;
|
|
var key;
|
|
if ( typeof obj !== 'object' || obj === null ) {
|
|
throw new TypeError( 'invalid argument. First argument must be an object. Value: `'+obj+'`.' );
|
|
}
|
|
if ( !isFunction( transform ) ) {
|
|
throw new TypeError( 'invalid argument. Second argument must be a function. Value: `'+transform+'`.' );
|
|
}
|
|
out = {};
|
|
for ( key in obj ) {
|
|
if ( hasOwnProp( obj, key ) ) {
|
|
out[ key ] = transform( obj[ key ], key, obj );
|
|
}
|
|
}
|
|
return out;
|
|
}
|
|
|
|
|
|
// EXPORTS //
|
|
|
|
module.exports = mapValues;
|