redux toolkit "flow types" code example

Example 1: redux toolkit

import { createSlice } from '@reduxjs/toolkit';

export const counterSlice = createSlice({
  name: 'counter',
  initialState: {
    value: 0,
  },
  reducers: {
    increment: state => { 
      state.value += 1;
    },
    decrement: state => {
      state.value -= 1;
    },
    incrementByAmount: (state, action) => {
      state.value += action.payload;
    },
  },
});

export const { increment, decrement, incrementByAmount } = counterSlice.actions;

export const selectCount = state => state.counter.value;

export default counterSlice.reducer;

Example 2: redux toolkit reducer

import {createAction, createReducer} from '@reduxjs/toolkit ;
//Action
const add = createAction('add');
//Reducer
const Reducer = createReducer(initialState= 0, (builder)=>{
  builder.addCase(add, (state,action) => state + 1)
})