34 lines
979 B
Plaintext
34 lines
979 B
Plaintext
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/**
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* Copyright (c) 2013-present, Facebook, Inc.
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*
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* This source code is licensed under the MIT license found in the
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* LICENSE file in the root directory of this source tree.
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*
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* @providesModule ExecutionEnvironment
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*/
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'use strict';
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const canUseDOM = !!(typeof window !== 'undefined' && window.document && window.document.createElement);
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/**
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* Simple, lightweight module assisting with the detection and context of
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* Worker. Helps avoid circular dependencies and allows code to reason about
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* whether or not they are in a Worker, even if they never include the main
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* `ReactWorker` dependency.
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*/
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const ExecutionEnvironment = {
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canUseDOM: canUseDOM,
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canUseWorkers: typeof Worker !== 'undefined',
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canUseEventListeners: canUseDOM && !!(window.addEventListener || window.attachEvent),
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canUseViewport: canUseDOM && !!window.screen,
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isInWorker: !canUseDOM // For now, this is true - might change in the future.
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};
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module.exports = ExecutionEnvironment;
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