time-to-botec

Benchmark sampling in different programming languages
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README.md (3658B)

      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 # ifelseAsync
     22 
     23 > If a predicate function returns a truthy value, return `x`; otherwise, return `y`.
     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 ifelseAsync = require( '@stdlib/utils/async/if-else' );
     41 ```
     42 
     43 #### ifelseAsync( predicate, x, y, done )
     44 
     45 If a `predicate` function returns a truthy value, returns `x`; otherwise, returns `y`.
     46 
     47 ```javascript
     48 var randu = require( '@stdlib/random/base/randu' );
     49 
     50 function predicate( clbk ) {
     51     setTimeout( onTimeout, 0 );
     52     function onTimeout() {
     53         clbk( null, randu() > 0.5 );
     54     }
     55 }
     56 
     57 function done( error, result ) {
     58     if ( error ) {
     59         throw error;
     60     }
     61     console.log( result );
     62 }
     63 
     64 ifelseAsync( predicate, 1.0, -1.0, done );
     65 ```
     66 
     67 The `predicate` function is provided a single argument:
     68 
     69 -   `clbk`: callback to invoke upon `predicate` function completion
     70 
     71 The callback accepts two arguments:
     72 
     73 -   `error`: error object
     74 -   `bool`: condition used to determine whether to return `x` or `y`
     75 
     76 The `done` callback is invoked upon function completion and is provided at most two arguments:
     77 
     78 -   `error`: error object
     79 -   `result`: either `x` or `y`
     80 
     81 </section>
     82 
     83 <!-- /.usage -->
     84 
     85 <!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
     86 
     87 <section class="notes">
     88 
     89 ## Notes
     90 
     91 -   Execution is **not** guaranteed to be asynchronous. To guarantee asynchrony, wrap the `done` callback in a function which either executes at the end of the current stack (e.g., `nextTick`) or during a subsequent turn of the event loop (e.g., `setImmediate`, `setTimeout`).
     92 
     93 </section>
     94 
     95 <!-- /.notes -->
     96 
     97 <!-- Package usage examples. -->
     98 
     99 <section class="examples">
    100 
    101 ## Examples
    102 
    103 <!-- eslint-disable callback-return -->
    104 
    105 <!-- eslint no-undef: "error" -->
    106 
    107 ```javascript
    108 var randu = require( '@stdlib/random/base/randu' );
    109 var ifelseAsync = require( '@stdlib/utils/async/if-else' );
    110 
    111 var i;
    112 
    113 function next() {
    114     ifelseAsync( predicate, 'BOOP', 'beep', done );
    115 }
    116 
    117 function predicate( clbk ) {
    118     setTimeout( onTimeout, 0 );
    119     function onTimeout() {
    120         clbk( null, randu() > 0.9 );
    121     }
    122 }
    123 
    124 function done( error, result ) {
    125     if ( error ) {
    126         throw error;
    127     }
    128     i += 1;
    129     console.log( result );
    130     if ( i < 100 ) {
    131         return next();
    132     }
    133 }
    134 
    135 i = 0;
    136 next();
    137 ```
    138 
    139 </section>
    140 
    141 <!-- /.examples -->
    142 
    143 <!-- 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. -->
    144 
    145 <section class="references">
    146 
    147 </section>
    148 
    149 <!-- /.references -->
    150 
    151 <!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
    152 
    153 <section class="links">
    154 
    155 </section>
    156 
    157 <!-- /.links -->