39 lines
1.1 KiB
JavaScript
39 lines
1.1 KiB
JavaScript
/**
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* Copyright (c) 2015-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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* @providesModule NavigationFindReducer
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* @flow
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*/
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'use strict';
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/*
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* NavigationFindReducer takes an array of reducers, and returns a reducer that
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* iterates through all of the reducers and the result of the first reducer
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* that modifies the input
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*/
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import type {
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NavigationState,
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NavigationReducer
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} from 'NavigationState';
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function NavigationFindReducer(reducers: Array<NavigationReducer>): ?NavigationReducer {
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return function(lastState: ?NavigationState, action: ?any): ?NavigationState {
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for (let i = 0; i < reducers.length; i++) {
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let reducer = reducers[i];
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let newState = reducer(lastState, action);
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if (newState !== lastState) {
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return newState;
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}
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}
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return lastState;
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};
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}
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module.exports = NavigationFindReducer;
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