384667ece1
* Added NOTICE.txt * Add creators to intro sentence * Removed react-addons-pure-render-mixin from NOTICE.txt since it's part of react * Copied fbjs keymirror into utils * Renamed deepFreezeAndThrowOnMutation to deep_freeze * Fixed merge conflict
44 lines
1.1 KiB
JavaScript
44 lines
1.1 KiB
JavaScript
/**
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* Copyright (c) 2013-present, Facebook, Inc.
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* All rights reserved.
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*
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* This source code is licensed under the BSD-style license found in the
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* LICENSE file in the root directory of this source tree. An additional grant
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* of patent rights can be found in the PATENTS file in the same directory.
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*
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*/
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/**
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* Constructs an enumeration with keys equal to their value.
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*
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* For example:
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*
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* var COLORS = keyMirror({blue: null, red: null});
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* var myColor = COLORS.blue;
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* var isColorValid = !!COLORS[myColor];
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*
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* The last line could not be performed if the values of the generated enum were
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* not equal to their keys.
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*
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* Input: {key1: val1, key2: val2}
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* Output: {key1: key1, key2: key2}
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*
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* @param {object} obj
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* @return {object}
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*/
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export default function keyMirror(obj) {
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if (!(obj instanceof Object && !Array.isArray(obj))) {
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throw new Error('keyMirror(...): Argument must be an object.');
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}
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const ret = {};
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for (const key in obj) {
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if (!obj.hasOwnProperty(key)) {
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continue;
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}
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ret[key] = key;
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}
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return ret;
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}
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