ExecutionEnvironment.js
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/**
* Copyright (c) 2015, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*
* @providesModule ExecutionEnvironment
*/
/*jslint evil: true */
'use strict';
var canUseDOM = !!(
typeof window !== 'undefined' &&
window.document &&
window.document.createElement
);
/**
* Simple, lightweight module assisting with the detection and context of
* Worker. Helps avoid circular dependencies and allows code to reason about
* whether or not they are in a Worker, even if they never include the main
* `ReactWorker` dependency.
*/
var ExecutionEnvironment = {
canUseDOM: canUseDOM,
canUseWorkers: typeof Worker !== 'undefined',
canUseEventListeners:
canUseDOM && !!(window.addEventListener || window.attachEvent),
canUseViewport: canUseDOM && !!window.screen,
isInWorker: !canUseDOM // For now, this is true - might change in the future.
};
module.exports = ExecutionEnvironment;