Architecting Angular Applications with Redux, RxJS, and NgRx

Adding the counter-list reducer

Let's start off with the reducer:

// counter/counter-list/counter-list.reducer.tsimport {  ADD_COUNTER_ITEM,  REMOVE_COUNTER_ITEM} from "./counter-list.constants";import { ActionPayload } from "../../action-payload";import { Counter } from "./counter.model";export function counterListReducer(state = [], action: ActionPayload<Counter>) {  switch (action.type) {    case ADD_COUNTER_ITEM:      return [...state, Object.assign(action.payload)];    case REMOVE_COUNTER_ITEM:      return state.filter(item => item.id !== action.payload.id);    default:      return state;  }}

This reducer supports two types, ADD_COUNTER_ITEM and REMOVE_COUNTER_ITEM, which will let us add and remove items from the list.