On Fri, Jan 05, 2007 at 06:14:31PM +0100, Bjorn Bringert wrote:
On Jan 5, 2007, at 18:04 , Ross Paterson wrote:
instance (MonadTrans t, MonadCGI m, Monad (t m)) => MonadCGI (t m)
I added that instance reluctantly, but it is quite useful when you write your own monad transformers and want to wrap CGIT. Removing it would break some existing code (Hope is the only one I know of),
Some of my code needs it too (I think I might have requested it be added in the first place?). I find it very useful to be able to write code in the style shown in http://www.haskell.org/pipermail/haskell-cafe/2007-January/021085.html Hugs compatibility is also important, though, and undecidable instances are marked "probably no" for Haskell'. It feels like a bit of a sledgehammer, but maybe the instance should be put in its own package cgi-undecidable or something? Thanks Ian