What is the prepare callback in createSlice and how is it used?

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In Redux Toolkit, the `prepare` callback allows you to **customize action’s payload** before it reaches the reducer. It is used inside a reducer definition within `createSlice()` and returns an object containing `payload`, and optionally, `meta` and `error` fields. To preprocess or format arguments before passing them as the action payload. To include additional fields such as timestamps or IDs along with the payload. To maintain clean reducer logic by separating payload creation from state updates. import { createSlice, nanoid } from '@reduxjs/toolkit';

export const { addTodo } = todosSlice.actions;
export default todosSlice.reducer; Here, the `prepare` callback formats the payload with an auto-generated ID and timestamp before the action reaches the reducer, keeping the reducer focused solely on updating the state.

What is the prepare callback in createSlice and how is it used?

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