Kapan sampeyan bakal nggunakno useReducer tinimbang useState?

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`useReducer` nggabungno state transitions ing sawijining **pure reducer function**, tinimbang nyebaraké akeh `useState` setters. Iki minangka versi built-in React saka Redux pattern. ```jsx function reducer(state, action) { switch (action.type) { case "increment": return { count: state.count + 1 }; case "setStep": return { ...state, step: action.payload }; case "reset": return { count: 0, step: 1 }; default: return state; } } function Counter() { const [state, dispatch] = useReducer(reducer, { count: 0, step: 1 }); // describe WHAT happened, not HOW state changes: return ; } ``` ## Carane gumana Sampeyan `dispatch` sawijining **action** (plain object sing nerangno kejadian). React nelpon `reducer(currentState, action)` lan nggunakno obyek sing mulih minangka state anyar. Reducer iku **pure** (ora ana side effects, ora ana mutation), sing nggawe logika predictable lan unit-testable ing ngasingé. ## Nalika luwih apik digunakno tinimbang useState - State sabanjure **gumantung ing state sadurungé** kanthi cara sing ora sederhana. - Pirang-pirang nilai **owah bareng-bareng** (conto `count` + `step` + `error`). - Update logic cukup rumit nganti sampeyan bakal baleni ing akeh handlers. ```jsx // instead of 4 separate useState + 6 setters, one reducer owns it all ``` Bonus: `dispatch` nduweni **stable identity**, dadi ngirim liwat context utawa menyang memoized children ora nyebabno re-renders. Kanggo nilai sederhana lan independen, plain `useState` isih luwih jelas.