GT2/GT2-iOS/node_modules/fbjs/lib/mapObject.js.flow

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/**
* Copyright (c) 2013-present, Facebook, Inc.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*
* @providesModule mapObject
*/
'use strict';
var hasOwnProperty = Object.prototype.hasOwnProperty;
/**
* Executes the provided `callback` once for each enumerable own property in the
* object and constructs a new object from the results. The `callback` is
* invoked with three arguments:
*
* - the property value
* - the property name
* - the object being traversed
*
* Properties that are added after the call to `mapObject` will not be visited
* by `callback`. If the values of existing properties are changed, the value
* passed to `callback` will be the value at the time `mapObject` visits them.
* Properties that are deleted before being visited are not visited.
*
* @grep function objectMap()
* @grep function objMap()
*
* @param {?object} object
* @param {function} callback
* @param {*} context
* @return {?object}
*/
function mapObject(object, callback, context) {
if (!object) {
return null;
}
var result = {};
for (var name in object) {
if (hasOwnProperty.call(object, name)) {
result[name] = callback.call(context, object[name], name, object);
}
}
return result;
}
module.exports = mapObject;