64 lines
1.3 KiB
JavaScript
64 lines
1.3 KiB
JavaScript
|
/**
|
||
|
|
* @license Apache-2.0
|
||
|
|
*
|
||
|
|
* Copyright (c) 2018 The Stdlib Authors.
|
||
|
|
*
|
||
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
||
|
|
* you may not use this file except in compliance with the License.
|
||
|
|
* You may obtain a copy of the License at
|
||
|
|
*
|
||
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
||
|
|
*
|
||
|
|
* Unless required by applicable law or agreed to in writing, software
|
||
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
||
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||
|
|
* See the License for the specific language governing permissions and
|
||
|
|
* limitations under the License.
|
||
|
|
*/
|
||
|
|
|
||
|
|
'use strict';
|
||
|
|
|
||
|
|
// MODULES //
|
||
|
|
|
||
|
|
var GlobalWeakMap = require( './weakmap.js' );
|
||
|
|
|
||
|
|
|
||
|
|
// MAIN //
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Tests for native `WeakMap` support.
|
||
|
|
*
|
||
|
|
* @returns {boolean} boolean indicating if an environment has `WeakMap` support
|
||
|
|
*
|
||
|
|
* @example
|
||
|
|
* var bool = hasWeakMapSupport();
|
||
|
|
* // returns <boolean>
|
||
|
|
*/
|
||
|
|
function hasWeakMapSupport() {
|
||
|
|
var bool;
|
||
|
|
var key;
|
||
|
|
var wm;
|
||
|
|
|
||
|
|
if ( typeof GlobalWeakMap !== 'function' ) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
// Test basic support...
|
||
|
|
try {
|
||
|
|
key = {};
|
||
|
|
wm = new GlobalWeakMap();
|
||
|
|
wm.set( key, 'beep' );
|
||
|
|
bool = (
|
||
|
|
wm.has( key ) &&
|
||
|
|
wm.get( key ) === 'beep'
|
||
|
|
);
|
||
|
|
} catch ( err ) { // eslint-disable-line no-unused-vars
|
||
|
|
bool = false;
|
||
|
|
}
|
||
|
|
return bool;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
// EXPORTS //
|
||
|
|
|
||
|
|
module.exports = hasWeakMapSupport;
|