I asked this question on StackOverflow and someone suggested using StateT. Unfortunately I don't think I can really carry around the state I'd like to:
http://stackoverflow.com/questions/6495320/hoopl-how-can-i-combine-the-checkingfuelmonad-with-a-state-monad On Fri, Jun 24, 2011 at 5:56 PM, Antoine Latter <[email protected]> wrote: > Hi Justin, this message might be better on the haskell-cafe list (or > the excellent beginers list!). > > When you tried to write the get/put implementations, what problems > were you running into? > > Antoine > > On Sat, Jun 25, 2011 at 7:50 AM, Justin Bailey <[email protected]> wrote: >> I'd like to carry around some state when rewriting. It seems like >> CheckingFuelMonad, etc. are set up to use with other monads but I >> can't get the types to agree. >> >> Using MTL I've managed to come up with these types: >> >>> newtype RewriteOnce a = R (State Bool a) >>> deriving (Monad) >>> >>> instance MonadState s (CheckingFuelMonad RewriteOnce) where >>> get = undefined >>> put = undefined >> >> >> But I cannot write the definitions for get and put. Is this possible >> or am I misundersanding CheckingFuelMonad? Is there a better approach >> altogether? >> >> Thanks in advance for any help! >> >> Justin >> >> _______________________________________________ >> Glasgow-haskell-users mailing list >> [email protected] >> http://www.haskell.org/mailman/listinfo/glasgow-haskell-users >> > _______________________________________________ Haskell-Cafe mailing list [email protected] http://www.haskell.org/mailman/listinfo/haskell-cafe
