time-to-botec

Benchmark sampling in different programming languages
Log | Files | Refs | README

README.md (2869B)

      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 # hasOwnProperty
     22 
     23 > Test if an object has a specified property.
     24 
     25 <section class="usage">
     26 
     27 ## Usage
     28 
     29 ```javascript
     30 var hasOwnProp = require( '@stdlib/assert/has-own-property' );
     31 ```
     32 
     33 #### hasOwnProp( value, property )
     34 
     35 Returns a `boolean` indicating if a `value` has a specified `property`.
     36 
     37 ```javascript
     38 var value = {
     39     'beep': 'boop'
     40 };
     41 
     42 var bool = hasOwnProp( value, 'beep' );
     43 // returns true
     44 
     45 bool = hasOwnProp( value, 'bap' );
     46 // returns false
     47 ```
     48 
     49 </section>
     50 
     51 <!-- /.usage -->
     52 
     53 <section class="notes">
     54 
     55 ## Notes
     56 
     57 -   In contrast to the native [Object.prototype.hasOwnProperty][mdn-object-has-own-property], this function does **not** throw when provided `null` or `undefined`. Instead, the function returns `false`.
     58 
     59     ```javascript
     60     var bool = hasOwnProp( null, 'a' );
     61     // returns false
     62 
     63     bool = hasOwnProp( void 0, 'a' );
     64     // returns false
     65     ```
     66 
     67 -   Value arguments other than `null` or `undefined` are coerced to `objects`.
     68 
     69     ```javascript
     70     var bool = hasOwnProp( 'beep', 'length' );
     71     // returns true
     72     ```
     73 
     74 -   Property arguments are coerced to `strings`.
     75 
     76     ```javascript
     77     var value = {
     78         'null': false
     79     };
     80     var bool = hasOwnProp( value, null );
     81     // returns true
     82 
     83     value = {
     84         '[object Object]': false
     85     };
     86     bool = hasOwnProp( value, {} );
     87     // returns true
     88     ```
     89 
     90 </section>
     91 
     92 <!-- /.notes -->
     93 
     94 <section class="examples">
     95 
     96 ## Examples
     97 
     98 <!-- eslint-disable object-curly-newline -->
     99 
    100 <!-- eslint no-undef: "error" -->
    101 
    102 ```javascript
    103 var hasOwnProp = require( '@stdlib/assert/has-own-property' );
    104 
    105 var bool = hasOwnProp( { 'a': 'b' }, 'a' );
    106 // returns true
    107 
    108 bool = hasOwnProp( { 'a': 'b' }, 'c' );
    109 // returns false
    110 
    111 bool = hasOwnProp( { 'a': 'b' }, null );
    112 // returns false
    113 
    114 bool = hasOwnProp( {}, 'hasOwnProperty' );
    115 // returns false
    116 
    117 bool = hasOwnProp( null, 'a' );
    118 // returns false
    119 
    120 bool = hasOwnProp( void 0, 'a' );
    121 // returns false
    122 
    123 bool = hasOwnProp( { 'null': false }, null );
    124 // returns true
    125 
    126 bool = hasOwnProp( { '[object Object]': false }, {} );
    127 // returns true
    128 ```
    129 
    130 </section>
    131 
    132 <!-- /.examples -->
    133 
    134 <section class="links">
    135 
    136 [mdn-object-has-own-property]: https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Object/hasOwnProperty
    137 
    138 </section>
    139 
    140 <!-- /.links -->