Looking at 2, if F is a delivery-person and my struct is a delivery truck, then the Monad will return a new delivery-person who can take the truck, extract a pa

Looking at 2, if F is a delivery-person and my struct is a delivery truck, then the Monad will return a new delivery-person who can take the truck, extract a parcel, pass it to the original delivery driver who will deliver it and the new delivery driver will get the signed delivery receipt, and put it in the truck. Am I getting close or just descending joyfully into madness?