Apa konsep inti saka Redux?

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**Redux** minangka container state sing bisa diprediksi sing dibangun kanthi telung prinsip pokok: **siji store**, **state sing mung bisa diwaca** sing bisa diubah mung liwat **actions**, lan **pure reducers** sing njitung state sabanjure. Data mili ing siji arah, nggawe owah-owahan bisa ditelusuri. ## Telung prinsip ```text 1. Single source of truth — the whole app's state lives in ONE store object 2. State is read-only — you never mutate it; you DISPATCH actions to change it 3. Changes via pure reducers — (state, action) => newState, no side effects ``` ## Potongan lan alur ```js // STORE — holds the single state tree const store = configureStore({ reducer: rootReducer }); // ACTION — a plain object describing what happened const action = { type: "counter/incremented", payload: 1 }; // REDUCER — pure function: given state + action, returns NEW state function counterReducer(state = { value: 0 }, action) { switch (action.type) { case "counter/incremented": return { ...state, value: state.value + action.payload }; // new object default: return state; } } // DISPATCH — the only way to trigger a change store.dispatch(action); // SELECT — read state store.getState().counter.value; ``` ## Siklus ```text UI dispatches an ACTION → REDUCER computes new STATE → STORE updates → subscribed components re-render → user interacts → dispatches the next action ``` Alur siji arah sing ketat iki ateges saben owah-owahan state minangka asil saka action sing didispatch lan diproses dening fungsi murni — bisa ditelusuri kabeh. ## Nggunaake ing React ```jsx import { useSelector, useDispatch } from "react-redux"; function Counter() { const count = useSelector(state => state.counter.value); // read const dispatch = useDispatch(); return ; // write } ``` ## Apa alasan batasan iki? ```text Predictability — every change is an explicit, logged action Debuggability — time-travel debugging, action replay (Redux DevTools) Testability — pure reducers are trivial to unit test ``` (Cathetan: Redux modern nggunakake **Redux Toolkit**, sing nyuda boilerplate banget amarga tetep nggawe konsep iki.) ## Apa gunane Konsep inti Redux — siji store, actions, pure reducers, alur siji arah — nggawe state aplikasi **bisa diprediksi lan bisa ditelusuri**, apa iki nilai utama kanggo aplikasi gedhe. Pamahaman tentang store/action/reducer/dispatch/select kudu dilakoni kanggo akeh codebase sing nggunakake Redux, lan prinsip-prinsip (pembaruan immutable, pure reducers, alur unidirecional) bali-bali muncul ing moro-moro kabeh perpustakaan state. Tukar rugi yaiku boilerplate, apa Redux Toolkit ngatasi kasambil njaga fondasi iki.