time-to-botec

Benchmark sampling in different programming languages
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README.md (3806B)

      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 # forOwn
     22 
     23 > Invoke a function for each own enumerable property of an object.
     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 forOwn = require( '@stdlib/utils/for-own' );
     41 ```
     42 
     43 #### forOwn( obj, fcn\[, thisArg ] )
     44 
     45 Invokes a `function` for each own enumerable property of an `object`.
     46 
     47 ```javascript
     48 function log( value, key ) {
     49     console.log( '%s: %d', key, value );
     50 }
     51 
     52 var obj = {
     53     'a': 1,
     54     'b': 2,
     55     'c': 3,
     56     'd': 4
     57 };
     58 
     59 forOwn( obj, log );
     60 /* e.g., =>
     61     a: 1
     62     b: 2
     63     c: 3
     64     d: 4
     65 */
     66 ```
     67 
     68 The invoked `function` is provided three arguments:
     69 
     70 -   `value`: object property value
     71 -   `key`: object property
     72 -   `obj`: the input object
     73 
     74 To terminate iteration before visiting all properties, the provided function must explicitly return `false`.
     75 
     76 ```javascript
     77 function log( value, key ) {
     78     console.log( '%s: %d', key, value );
     79     return false;
     80 }
     81 
     82 var obj = {
     83     'a': 1,
     84     'b': 2,
     85     'c': 3,
     86     'd': 4
     87 };
     88 
     89 forOwn( obj, log );
     90 // e.g., => a: 1
     91 ```
     92 
     93 To set the function execution context, provide a `thisArg`.
     94 
     95 ```javascript
     96 function sum( value ) {
     97     this.sum += value;
     98     this.count += 1;
     99 }
    100 
    101 var obj = {
    102     'a': 1,
    103     'b': 2,
    104     'c': 3,
    105     'd': 4
    106 };
    107 
    108 var context = {
    109     'sum': 0,
    110     'count': 0
    111 };
    112 
    113 forOwn( obj, sum, context );
    114 
    115 var mean = context.sum / context.count;
    116 // returns 2.5
    117 ```
    118 
    119 </section>
    120 
    121 <!-- /.usage -->
    122 
    123 <!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
    124 
    125 <section class="notes">
    126 
    127 ## Notes
    128 
    129 -   The function returns the input `object`.
    130 -   The function determines the list of own enumerable properties **before** invoking the provided function. Hence, any modifications made to the input `object` **after** calling this function (such as adding and removing properties) will **not** affect the list of visited properties.
    131 -   Property iteration order is **not** guaranteed.
    132 
    133 </section>
    134 
    135 <!-- /.notes -->
    136 
    137 <!-- Package usage examples. -->
    138 
    139 <section class="examples">
    140 
    141 ## Examples
    142 
    143 <!-- eslint no-undef: "error" -->
    144 
    145 ```javascript
    146 var fromCodePoint = require( '@stdlib/string/from-code-point' );
    147 var forOwn = require( '@stdlib/utils/for-own' );
    148 
    149 function update( value, key, obj ) {
    150     console.log( '%s: %d', key, value );
    151     obj[ key ] *= value;
    152 }
    153 
    154 var obj;
    155 var key;
    156 var i;
    157 
    158 obj = {};
    159 for ( i = 0; i < 26; i++ ) {
    160     key = fromCodePoint( 97 + i );
    161     obj[ key ] = i;
    162 }
    163 
    164 forOwn( obj, update );
    165 console.log( obj );
    166 ```
    167 
    168 </section>
    169 
    170 <!-- /.examples -->
    171 
    172 <!-- 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. -->
    173 
    174 <section class="references">
    175 
    176 </section>
    177 
    178 <!-- /.references -->
    179 
    180 <!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
    181 
    182 <section class="links">
    183 
    184 </section>
    185 
    186 <!-- /.links -->