.map not is not a function on empty object?

I am new to react. I have set up a reducer with the state as an empty object. But when using the .map() function it doesn’t seem to work on the object? Does the .map only work on arrays?

export const orders = (state = {}, action) => {
  const { type, payload } = action;

  switch (type) {
    case "NEW_ORDER":
      const { new_order } = payload;
      const new_state = { ...state, new_order };
      return new_state;
  return state;


Well, no, you can not use .map() on an object since it is supposed to be used in an array. By the way, if you are trying to store a list of orders, you should use am array instead, so initialize your state with [] and not with {}, or with a key that actually contains your orders like { orders: [] } and then add the order you received like const new_state = { ...state, orders: [...state.orders, new_order] }.