Typescript: declare ReturnType for all functions in a file (how to create a redux action type)

Question

I would like to create a ReturnType for all functions in a file.

For example, for redux actions file:

// files.actions.ts

export const setFiles = (files: IFile[]) => ({
    type: FILES_ACTION_TYPE.SET_FILES,
    payload: files,
});

export const clearFiles = () => ({
    type: FILES_ACTION_TYPE.CLEAR_FILES,
    payload: undefined
});

export type FilesAction = ReturnType<typeof clearFiles | typeof setFiles>

Is there an elegant way to have types of all the functions without writing each of them by hand?

Answer 1

While this isn't a direct answer to your question:

We would specifically recommend not writing action creators by hand. Instead, you should use the createSlice API from our official Redux Toolkit package , as it automatically generates action creators for you. It's also already written in TS, and ensures that the action creators are correctly typed to match the reducers.

Related to that, I personally see no real benefit to attempting to define a union type of all actions that can be dispatched, or limiting the set of actions that can be passed to dispatch .