time-to-botec

Benchmark sampling in different programming languages
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main.js (2160B)

      1 /**
      2 * @license Apache-2.0
      3 *
      4 * Copyright (c) 2018 The Stdlib Authors.
      5 *
      6 * Licensed under the Apache License, Version 2.0 (the "License");
      7 * you may not use this file except in compliance with the License.
      8 * You may obtain a copy of the License at
      9 *
     10 *    http://www.apache.org/licenses/LICENSE-2.0
     11 *
     12 * Unless required by applicable law or agreed to in writing, software
     13 * distributed under the License is distributed on an "AS IS" BASIS,
     14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     15 * See the License for the specific language governing permissions and
     16 * limitations under the License.
     17 */
     18 
     19 'use strict';
     20 
     21 // VARIABLES //
     22 
     23 /**
     24 * Detects a JSON string.
     25 *
     26 * Regular expression: `/^\{[\s\S]*\}$|^\[[\s\S]*\]$/`
     27 *
     28 * -   `^\{`
     29 *
     30 *     -   match a `{` literal which is the first character
     31 *
     32 * -   `[\s\S]*`
     33 *
     34 *     -   match any whitespace and non-whitespace characters which occur `0` or more times
     35 *
     36 * -   `\}$`
     37 *
     38 *     -   match a `}` literal which is the last character
     39 *
     40 * -   `|`
     41 *
     42 *     -   alternatively
     43 *
     44 * -   `^\[`
     45 *
     46 *     -   match a `[` literal which is the first character
     47 *
     48 * -   `[\s\S]*`
     49 *
     50 *     -   match any whitespace and non-whitespace characters which occur `0` or more times
     51 *
     52 * -   `\]$`
     53 *
     54 *     -   match a `]` literal which is the last character
     55 *
     56 *
     57 * Example matching strings:
     58 *
     59 * -   `'{}'`
     60 * -   `'[]'`
     61 * -   `'{adjlkfaj3743.,><\n\t\rdf}'`
     62 * -   `'[adjlkfaj3743.,><\n\t\rdf]'`
     63 * -   `'{"a":5}'`
     64 *
     65 * @constant
     66 * @type {RegExp}
     67 * @default /^\{[\s\S]*\}$|^\[[\s\S]*\]$/
     68 */
     69 var re = /^\{[\s\S]*\}$|^\[[\s\S]*\]$/;
     70 
     71 
     72 // MAIN //
     73 
     74 /**
     75 * Tests if a value is a parseable JSON string.
     76 *
     77 * @param {*} value - value to test
     78 * @returns {boolean} boolean indicating if a value is a parseable JSON string
     79 *
     80 * @example
     81 * var v = isJSON( '{"a":5}' );
     82 * // returns true
     83 *
     84 * @example
     85 * var v = isJSON( '{a":5}' );
     86 * // returns false
     87 */
     88 function isJSON( value ) {
     89 	if ( typeof value !== 'string' ) {
     90 		return false;
     91 	}
     92 	if ( !re.test( value ) ) {
     93 		return false;
     94 	}
     95 	try {
     96 		JSON.parse( value );
     97 	} catch ( err ) { // eslint-disable-line no-unused-vars
     98 		return false;
     99 	}
    100 	return true;
    101 }
    102 
    103 
    104 // EXPORTS //
    105 
    106 module.exports = isJSON;