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authorFlorian Dold <florian.dold@gmail.com>2017-05-03 15:35:00 +0200
committerFlorian Dold <florian.dold@gmail.com>2017-05-03 15:35:00 +0200
commitde98e0b232509d5f40c135d540a70e415272ff85 (patch)
treea79222a5b58484ab3b80d18efcaaa7ccc4769b33 /node_modules/fbjs/lib/ExecutionEnvironment.js.flow
parente0c9d480a73fa629c1e4a47d3e721f1d2d345406 (diff)
node_modules
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+/**
+ * Copyright (c) 2013-present, 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
+ */
+
+'use strict';
+
+const 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.
+ */
+const 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; \ No newline at end of file