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46 lines
1.4 KiB
46 lines
1.4 KiB
2 days ago
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import { createContext, Dispatch, ReactNode, useContext, useReducer } from 'react';
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type State = { count: number };
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type Action = { type: 'INCREMENT' | 'DECREMENT' };
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const initialState: State = { count: 0 };
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function counterReducer(state: State, action: Action): State {
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switch (action.type) {
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case 'INCREMENT':
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return { count: state.count + 1 };
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case 'DECREMENT':
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return { count: state.count - 1 };
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default:
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throw new Error('Unhandled action');
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}
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}
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const CounterStateContext = createContext<State | undefined>(undefined);
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const CounterDispatchContext = createContext<Dispatch<Action> | undefined>(undefined);
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export function CounterProvider({ children }: { children: ReactNode }) {
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const [state, dispatch] = useReducer(counterReducer, initialState);
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return (
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<CounterStateContext.Provider value={state}>
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<CounterDispatchContext.Provider value={dispatch}>{children}</CounterDispatchContext.Provider>
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</CounterStateContext.Provider>
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);
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}
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export function useCounterState() {
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const context = useContext(CounterStateContext);
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if (context === undefined)
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throw new Error('useCounterState must be used within a CounterProvider');
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return context;
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}
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export function useCounterDispatch() {
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const context = useContext(CounterDispatchContext);
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if (context === undefined)
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throw new Error('useCounterDispatch must be used within a CounterProvider');
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return context;
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}
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