time-to-botec

Benchmark sampling in different programming languages
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README.md (4105B)

      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 # trycatchAsync
     22 
     23 > If a function does not return an error, invoke a callback with the function result; otherwise, invoke a callback with a value `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 trycatchAsync = require( '@stdlib/utils/async/try-catch' );
     41 ```
     42 
     43 #### trycatchAsync( x, y, done )
     44 
     45 If a function `x` does not return an error, invokes a `done` callback with the function result; otherwise, invokes a `done` callback with a value `y`.
     46 
     47 ```javascript
     48 var randu = require( '@stdlib/random/base/randu' );
     49 
     50 function x( clbk ) {
     51     setTimeout( onTimeout, 0 );
     52     function onTimeout() {
     53         if ( randu() > 0.5 ) {
     54             return clbk( null, 1.0 );
     55         }
     56         clbk( new Error( 'oops' ) );
     57     }
     58 }
     59 
     60 function done( error, result ) {
     61     if ( error ) {
     62         console.log( error.message );
     63     }
     64     console.log( result );
     65 }
     66 
     67 trycatchAsync( x, -1.0, done );
     68 ```
     69 
     70 The function `x` is provided a single argument:
     71 
     72 -   `clbk`: callback to invoke upon function completion
     73 
     74 The callback accepts two arguments:
     75 
     76 -   `error`: error object
     77 -   `result`: function result
     78 
     79 The `done` callback is invoked upon function completion and is provided two arguments:
     80 
     81 -   `error`: error object
     82 -   `result`: either the result of `x` or the provided value `y`
     83 
     84 If the function `x` does not return a truthy `error` argument, the `error` argument provided to the `done` callback is `null`. If `x` does return a truthy `error` argument, the `done` callback is invoked with both the `error` and the provided value `y`.
     85 
     86 </section>
     87 
     88 <!-- /.usage -->
     89 
     90 <!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
     91 
     92 <section class="notes">
     93 
     94 ## Notes
     95 
     96 -   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`).
     97 
     98 </section>
     99 
    100 <!-- /.notes -->
    101 
    102 <!-- Package usage examples. -->
    103 
    104 <section class="examples">
    105 
    106 ## Examples
    107 
    108 <!-- eslint no-undef: "error" -->
    109 
    110 ```javascript
    111 var randu = require( '@stdlib/random/base/randu' );
    112 var trycatchAsync = require( '@stdlib/utils/async/try-catch' );
    113 
    114 var i;
    115 
    116 function next() {
    117     trycatchAsync( x, 'beep', done );
    118 }
    119 
    120 function x( clbk ) {
    121     setTimeout( onTimeout, 0 );
    122     function onTimeout() {
    123         if ( randu() > 0.9 ) {
    124             return clbk( null, 'BOOP' );
    125         }
    126         clbk( new Error( 'oops' ) );
    127     }
    128 }
    129 
    130 function done( error, result ) {
    131     if ( error ) {
    132         console.log( error.message );
    133     }
    134     i += 1;
    135     console.log( result );
    136     if ( i < 100 ) {
    137         return next();
    138     }
    139 }
    140 
    141 i = 0;
    142 next();
    143 ```
    144 
    145 </section>
    146 
    147 <!-- /.examples -->
    148 
    149 <!-- 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. -->
    150 
    151 <section class="references">
    152 
    153 </section>
    154 
    155 <!-- /.references -->
    156 
    157 <!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
    158 
    159 <section class="links">
    160 
    161 </section>
    162 
    163 <!-- /.links -->