time-to-botec

Benchmark sampling in different programming languages
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README.md (2115B)

      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 # Constant Function
     22 
     23 > Constant function.
     24 
     25 <section class="intro">
     26 
     27 A [constant function][constant-function] is a `function` whose output value is the same for every input value.
     28 
     29 </section>
     30 
     31 <!-- /.intro -->
     32 
     33 <section class="usage">
     34 
     35 ## Usage
     36 
     37 ```javascript
     38 var constantFunction = require( '@stdlib/utils/constant-function' );
     39 ```
     40 
     41 #### constantFunction( x )
     42 
     43 Returns a [constant function][constant-function] which always returns `x`.
     44 
     45 ```javascript
     46 var fcn = constantFunction( 'beep' );
     47 // returns <Function>
     48 
     49 var v = fcn();
     50 // returns 'beep'
     51 
     52 v = fcn();
     53 // returns 'beep'
     54 ```
     55 
     56 </section>
     57 
     58 <!-- /.usage -->
     59 
     60 <section class="notes">
     61 
     62 ## Notes
     63 
     64 -   When provided an object reference, the returned `function` always returns the same reference.
     65 
     66     ```javascript
     67     var obj = {};
     68     var fcn = constantFunction( obj );
     69 
     70     var bool = ( fcn() === obj );
     71     // returns true
     72     ```
     73 
     74 </section>
     75 
     76 <!-- /.notes -->
     77 
     78 <section class="examples">
     79 
     80 ## Examples
     81 
     82 <!-- eslint no-undef: "error" -->
     83 
     84 ```javascript
     85 var constantFunction = require( '@stdlib/utils/constant-function' );
     86 
     87 var bool;
     88 var fcn;
     89 var arr;
     90 var v;
     91 var i;
     92 
     93 fcn = constantFunction( 3.14 );
     94 for ( i = 0; i < 10; i++ ) {
     95     v = fcn();
     96     // returns 3.14
     97 }
     98 
     99 arr = [ 1, 2, 3 ];
    100 fcn = constantFunction( arr );
    101 for ( i = 0; i < 10; i++ ) {
    102     v = fcn();
    103     bool = ( v === arr );
    104     // returns true
    105 }
    106 ```
    107 
    108 </section>
    109 
    110 <!-- /.examples -->
    111 
    112 <section class="links">
    113 
    114 [constant-function]: https://en.wikipedia.org/wiki/Constant_function
    115 
    116 </section>
    117 
    118 <!-- /.links -->