Hi, Additionally, it would be very useful to have the MaybeT monad transformer included into mtl-2. While migrating my packages from transformers/monads-fd to the new mtl, the absence of MaybeT was the only problem I came across. Cheers, Sebastiaan On Nov 6, 2010, at 3:26 PM, Ross Paterson wrote:
On Tue, Nov 02, 2010 at 02:17:03PM +0100, Johan Tibell wrote:
This is a call for consensus for the following proposal:
http://trac.haskell.org/haskell-platform/wiki/Proposals/transformers
Are there any unresolved concerns?
Brent Yorgey's report raises one: the following functions, defined in the transformers package as replacements for data constructors for the base monads, should probably be re-exported by the new mtl:
Control.Monad.Cont: cont :: ((a -> r) -> r) -> Cont r a Control.Monad.RWS.Lazy: rws :: (r -> s -> (a, s, w)) -> RWS r w s a Control.Monad.RWS.Strict: rws :: (r -> s -> (a, s, w)) -> RWS r w s a Control.Monad.Reader: reader :: (r -> a) -> Reader r a Control.Monad.State.Lazy: state :: (s -> (a, s)) -> State s a Control.Monad.State.Strict: state :: (s -> (a, s)) -> State s a Control.Monad.Writer.Lazy: writer :: (a, w) -> Writer w a Control.Monad.Writer.Strict: writer :: (a, w) -> Writer w a