Triplet action creators for async API fetch in Redux

ordersActions.js

// duck/ordersActions.js
export const FETCH_ORDERS_REQUEST = 'FETCH_ORDERS_REQUEST'
export const FETCH_ORDERS_SUCCESS = 'FETCH_ORDERS_SUCCESS'
export const FETCH_ORDERS_ERROR = 'FETCH_ORDERS_ERROR'

export const fetchOrdersRequest = _ => ({ // _ = ()
  type: FETCH_ORDERS_REQUEST
  // no payload
})

export const fetchOrdersSuccess = orders => ({
  type: FETCH_ORDERS_SUCCESS,
  payload: { orders } // same as 'payload: { orders: orders }'
})

export const fetchOrdersError = error => ({
  type: FETCH_ORDERS_ERROR,
  payload: { error }
})