On Sat, 2009-11-28 at 16:56 +0000, Ross Paterson wrote:
On Sat, Nov 28, 2009 at 04:40:49PM +0000, Duncan Coutts wrote:
Could someone remind me why it's better for use to ask everyone to switch to monads-fd / transformers rather than to mtl-2? Does that make the transition easier?
The problem is that transformers and mtl use the same module names, such as Control.Monad.Identity. Unless one of these packages is hidden, people using ghci or ghc --make will have problems.
Right, so having transformers + mtl is bad, but why do we want to end up with a situation where we have both? If you've all agreed what should go into the new monad package, can't we call that mtl-2 ? Why would we want to define things in one package and re-export them in another? Duncan