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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.
+ *
+ * @typechecks static-only
+ */
+
+'use strict';
+
+var invariant = require('./invariant');
+
+/**
+ * Constructs an enumeration with keys equal to their value.
+ *
+ * For example:
+ *
+ * var COLORS = keyMirror({blue: null, red: null});
+ * var myColor = COLORS.blue;
+ * var isColorValid = !!COLORS[myColor];
+ *
+ * The last line could not be performed if the values of the generated enum were
+ * not equal to their keys.
+ *
+ * Input: {key1: val1, key2: val2}
+ * Output: {key1: key1, key2: key2}
+ *
+ * @param {object} obj
+ * @return {object}
+ */
+var keyMirror = function keyMirror(obj) {
+ var ret = {};
+ var key;
+ !(obj instanceof Object && !Array.isArray(obj)) ? process.env.NODE_ENV !== 'production' ? invariant(false, 'keyMirror(...): Argument must be an object.') : invariant(false) : void 0;
+ for (key in obj) {
+ if (!obj.hasOwnProperty(key)) {
+ continue;
+ }
+ ret[key] = key;
+ }
+ return ret;
+};
+
+module.exports = keyMirror; \ No newline at end of file