time-to-botec

Benchmark sampling in different programming languages
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main.js (1412B)

      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 /**
     22 * Tests if a value is `undefined` or `null`.
     23 *
     24 * ## Notes
     25 *
     26 * -   In older browsers, `undefined` is a global which can be overridden. `void`, however, is an operator which **cannot** be overridden. Consequently, better to use `void` to check for `undefined`. See [Stack Overflow][1].
     27 *
     28 * [1]: http://stackoverflow.com/a/19369078/2225624
     29 *
     30 * @param {*} value - value to test
     31 * @returns {boolean} boolean indicating whether value is undefined
     32 *
     33 * @example
     34 * var bool = isUndefinedOrNull( undefined );
     35 * // returns true
     36 *
     37 * bool = isUndefinedOrNull( null );
     38 * // returns true
     39 *
     40 * bool = isUndefinedOrNull( false );
     41 * // returns false
     42 */
     43 function isUndefinedOrNull( value ) {
     44 	return ( value === void 0 || value === null );
     45 }
     46 
     47 
     48 // EXPORTS //
     49 
     50 module.exports = isUndefinedOrNull;