Listening actions in different reducers

listening_actions.js

function usersReducer (state = Map(), action) {
  switch (action.type) {
    ...
    case REMOVE_USER:
      return state.delete(action.id)
    ...
  }
}

function tasksReducer (state = Map(), action) {
  switch (action.type) {
    ...
    case REMOVE_USER:
      return state.filter(task => task.user_id !== action.id)
    ...
  }
}