react / useReducer

Function: useReducer()#

useReducer(reducer, initializerArg, initializer)#

function useReducer<R, I>(
   reducer: R,
   initializerArg: I,
   initializer: (arg: I) => ReducerStateWithoutAction<R>): [ReducerStateWithoutAction<R>, DispatchWithoutAction]

An alternative to useState.

useReducer is usually preferable to useState when you have complex state logic that involves multiple sub-values. It also lets you optimize performance for components that trigger deep updates because you can pass dispatch down instead of callbacks.

Type Parameters#

Parameters#

Returns#

[ReducerStateWithoutAction<R>, DispatchWithoutAction]

Version#

16.8.0

See#

https://react.dev/reference/react/useReducer

Defined in#

.pnpm/@types+react@18.3.11/node_modules/@types/react/ts5.0/index.d.ts:1896

useReducer(reducer, initializerArg, initializer)#

function useReducer<R>(
   reducer: R,
   initializerArg: ReducerStateWithoutAction<R>,
   initializer?: undefined): [ReducerStateWithoutAction<R>, DispatchWithoutAction]

An alternative to useState.

useReducer is usually preferable to useState when you have complex state logic that involves multiple sub-values. It also lets you optimize performance for components that trigger deep updates because you can pass dispatch down instead of callbacks.

Type Parameters#

Parameters#

Returns#

[ReducerStateWithoutAction<R>, DispatchWithoutAction]

Version#

16.8.0

See#

https://react.dev/reference/react/useReducer

Defined in#

.pnpm/@types+react@18.3.11/node_modules/@types/react/ts5.0/index.d.ts:1912

useReducer(reducer, initializerArg, initializer)#

function useReducer<R, I>(
   reducer: R,
   initializerArg: I & ReducerState<R>,
   initializer: (arg: I & ReducerState<R>) => ReducerState<R>): [ReducerState<R>, Dispatch<ReducerAction<R>>]

An alternative to useState.

useReducer is usually preferable to useState when you have complex state logic that involves multiple sub-values. It also lets you optimize performance for components that trigger deep updates because you can pass dispatch down instead of callbacks.

Type Parameters#

Parameters#

Returns#

[ReducerState<R>, Dispatch<ReducerAction<R>>]

Version#

16.8.0

See#

https://react.dev/reference/react/useReducer

Defined in#

.pnpm/@types+react@18.3.11/node_modules/@types/react/ts5.0/index.d.ts:1930

useReducer(reducer, initializerArg, initializer)#

function useReducer<R, I>(
   reducer: R,
   initializerArg: I,
   initializer: (arg: I) => ReducerState<R>): [ReducerState<R>, Dispatch<ReducerAction<R>>]

An alternative to useState.

useReducer is usually preferable to useState when you have complex state logic that involves multiple sub-values. It also lets you optimize performance for components that trigger deep updates because you can pass dispatch down instead of callbacks.

Type Parameters#

Parameters#

Returns#

[ReducerState<R>, Dispatch<ReducerAction<R>>]

Version#

16.8.0

See#

https://react.dev/reference/react/useReducer

Defined in#

.pnpm/@types+react@18.3.11/node_modules/@types/react/ts5.0/index.d.ts:1946

useReducer(reducer, initialState, initializer)#

function useReducer<R>(
   reducer: R,
   initialState: ReducerState<R>,
   initializer?: undefined): [ReducerState<R>, Dispatch<ReducerAction<R>>]

An alternative to useState.

useReducer is usually preferable to useState when you have complex state logic that involves multiple sub-values. It also lets you optimize performance for components that trigger deep updates because you can pass dispatch down instead of callbacks.

Type Parameters#

Parameters#

Returns#

[ReducerState<R>, Dispatch<ReducerAction<R>>]

Version#

16.8.0

See#

https://react.dev/reference/react/useReducer

Defined in#

.pnpm/@types+react@18.3.11/node_modules/@types/react/ts5.0/index.d.ts:1971