We have yet to create the dispatch() method, so we will do that next:

// dataflow/redux.js

export function dispatch(action) {
  // implement this
}

What we can see from the preceding code is that we have a dispatch() function, which is one of the things we export from this file. Let's try to fill in the implementation:

// dataflow/redux-stepI.js

// 1)
function itemsReducer(state = [], action) {
  switch(action.type) {
    case "CREATE_ITEM":
      return [...state, Object.assign(action.payload) ];
    default: 
      return state;
  }    
}

// 2)
let state = {
  items: []
};

// 3
function store(state = { items: [] }, action) {
  return {
    items: itemsReducer(state.items, action)
  };
}

// 4)
export function getState() {
  return state;
}

// 5)
export function dispatch(action) {
  state = store(state, action);
}

Let's explain what we did there from the top. We first define a reducer 1) called itemsReducer,  which can produce a new state given a new item. Thereafter, we create a state variable, which is our state 2). This is followed by the store() function 3), which is a function to set up which property goes together with which reducer. Thereafter, we define a function called getState() 4), which returns our current state. Lastly, we have our dispatch() function 5), which just invokes the store() function with the action we provide it.