time-to-botec

Benchmark sampling in different programming languages
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README.md (3238B)

      1 <!--
      2 
      3 @license Apache-2.0
      4 
      5 Copyright (c) 2018 The Stdlib Authors.
      6 
      7 Licensed under the Apache License, Version 2.0 (the "License");
      8 you may not use this file except in compliance with the License.
      9 You may obtain a copy of the License at
     10 
     11    http://www.apache.org/licenses/LICENSE-2.0
     12 
     13 Unless required by applicable law or agreed to in writing, software
     14 distributed under the License is distributed on an "AS IS" BASIS,
     15 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     16 See the License for the specific language governing permissions and
     17 limitations under the License.
     18 
     19 -->
     20 
     21 # mapValues
     22 
     23 > Map values from one object to a new object having the same keys.
     24 
     25 <!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->
     26 
     27 <section class="intro">
     28 
     29 </section>
     30 
     31 <!-- /.intro -->
     32 
     33 <!-- Package usage documentation. -->
     34 
     35 <section class="usage">
     36 
     37 ## Usage
     38 
     39 ```javascript
     40 var mapValues = require( '@stdlib/utils/map-values' );
     41 ```
     42 
     43 #### mapValues( obj, transform )
     44 
     45 Map values from one `object` to a new `object` having the same keys.
     46 
     47 ```javascript
     48 function transform( value, key ) {
     49     return key + value;
     50 }
     51 
     52 var obj1 = {
     53     'a': 1,
     54     'b': 2
     55 };
     56 
     57 var obj2 = mapValues( obj1, transform );
     58 // returns { 'a': 'a1', 'b': 'b2' }
     59 ```
     60 
     61 The `transform` function is provided three arguments:
     62 
     63 -   `value`: object value corresponding to `key`
     64 -   `key`: object key
     65 -   `obj`: the input object
     66 
     67 </section>
     68 
     69 <!-- /.usage -->
     70 
     71 <!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
     72 
     73 <section class="notes">
     74 
     75 ## Notes
     76 
     77 -   Key iteration order is **not** guaranteed, as `object` key enumeration is not specified according to the [ECMAScript specification][ecma-262-for-in]. In practice, however, most engines use insertion order to sort an `object`'s keys, thus allowing for deterministic return values.
     78 -   The function only maps values assigned to **own** properties. Hence, the function does **not** map values for inherited properties.
     79 -   The function **shallow** copies key values.
     80 
     81 </section>
     82 
     83 <!-- /.notes -->
     84 
     85 <!-- Package usage examples. -->
     86 
     87 <section class="examples">
     88 
     89 ## Examples
     90 
     91 <!-- eslint no-undef: "error" -->
     92 
     93 ```javascript
     94 var mapValues = require( '@stdlib/utils/map-values' );
     95 
     96 function transform( value, key ) {
     97     return key + ':' + value;
     98 }
     99 
    100 var obj1 = {
    101     'a': 'beep',
    102     'b': 'boop',
    103     'c': 'foo',
    104     'd': 'bar'
    105 };
    106 
    107 var obj2 = mapValues( obj1, transform );
    108 
    109 console.dir( obj2 );
    110 // => { 'a': 'a:beep', 'b': 'b:boop', 'c': 'c:foo', 'd': 'd:bar' }
    111 ```
    112 
    113 </section>
    114 
    115 <!-- /.examples -->
    116 
    117 <!-- Section to include cited references. If references are included, add a horizontal rule *before* the section. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
    118 
    119 <section class="references">
    120 
    121 </section>
    122 
    123 <!-- /.references -->
    124 
    125 <!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
    126 
    127 <section class="links">
    128 
    129 [ecma-262-for-in]: http://www.ecma-international.org/ecma-262/5.1/#sec-12.6.4
    130 
    131 </section>
    132 
    133 <!-- /.links -->