main.js (1340B)
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 // MODULES // 22 23 var GlobalWeakMap = require( './weakmap.js' ); 24 25 26 // MAIN // 27 28 /** 29 * Tests for native `WeakMap` support. 30 * 31 * @returns {boolean} boolean indicating if an environment has `WeakMap` support 32 * 33 * @example 34 * var bool = hasWeakMapSupport(); 35 * // returns <boolean> 36 */ 37 function hasWeakMapSupport() { 38 var bool; 39 var key; 40 var wm; 41 42 if ( typeof GlobalWeakMap !== 'function' ) { 43 return false; 44 } 45 // Test basic support... 46 try { 47 key = {}; 48 wm = new GlobalWeakMap(); 49 wm.set( key, 'beep' ); 50 bool = ( 51 wm.has( key ) && 52 wm.get( key ) === 'beep' 53 ); 54 } catch ( err ) { // eslint-disable-line no-unused-vars 55 bool = false; 56 } 57 return bool; 58 } 59 60 61 // EXPORTS // 62 63 module.exports = hasWeakMapSupport;