On Wed, 25 Feb 2009, Jean-Philippe Bernardy wrote:
> On Wed, Feb 25, 2009 at 12:53 AM, Henning Thielemann > <lemm...@henning-thielemann.de> wrote: > >> Thanks for your interest in data-accessor ... > > It's a very useful package! My previous email was written in haste, > I should have mentioned how much the template-haskell stuff saved > effort in boilerplate. That's Luke Palmer's work. :-) >> What functions do you mean? I'm not aware that I have specialised some >> function types. I have however rewritten the MonadState part from 'mtl' >> package to 'transformers'. Is this your problem? > > I guess it is related. It is possible that I do not know how to use > 'transformers' properly. > Specifically: > > http://hackage.haskell.org/packages/archive/data-accessor/0.1.4/doc/html/Data-Accessor.html > > getA :: MonadState r m => Accessor r a -> m a > > http://hackage.haskell.org/packages/archive/data-accessor/0.2.0.2/doc/html/Data-Accessor.html > > getA :: Monad m => Accessor r a -> StateT r m a > > I'd rather not rewrite the monads to the StateT form... > I'm now writing a compatibility layer, but I feel it would be better if > the data-accessor package supported the old interface. In 'transformers', State r = StateT r Identity, thus there is no need for the MonadState class, which is not Haskell 98. I could reactivate the old MonadState module and publish it as MonadState.MTL in a separate package. --~--~---------~--~----~------------~-------~--~----~ Yi development mailing list yi-devel@googlegroups.com http://groups.google.com/group/yi-devel -~----------~----~----~----~------~----~------~--~---
