Hey Everyone, I am having a hard time making a data structure that I can incrimentally update. Mostly because dealing with arrays is so tough. Does anyone think I'm going about this completely the wrong way? This is what I have. data GameState = GameState { dTickets :: Array Player (Array Ticket Int), fTickets :: Array FugitiveTicket Int, history :: [Move], dLocations :: Array Player Stop, fLocations :: Set Stop } removeTicket :: GameState -> Detective -> Ticket -> GameState removeTicket s d t = s { tickets = (tickets s) // [(d,[(t,((tickets s)!d!t - 1))])] } This remove ticket function is just terrible and it's common for me to have to do operations like this. It's been hard to make this a function that I can pattern match on, because which piece of data is manipulated depends on the parmeter d (Detective) Incase you all didn't notice, I decided to write a game in Haskell to learn it. Thanks for all the useful help. I should know Haskell pretty well by the end of all this. -mike