On Mon, 5 Jan 2009, Ross Paterson wrote:
On Mon, Jan 05, 2009 at 09:32:21AM +0100, Henning Thielemann wrote:
How about Control.Monad.Trans.Identity which is re-exported by Control.Monad.Identity in mtl?
Hmm, it's a conflict between co-existing with mtl and using the Right Name for the transformers package, which is intended to be usable by itself. I prefer the latter, myself.
You mean that Control.Monad.Trans.Identity is not a good name, because Identity is not a transformer? Then, how about Control.Monad.Base.Identity, Control.Monad.Primitive.Identity or so? Since mtl-split is not a drop-in replacement for mtl, we cannot expect a quick change from mtl to mtl-split in all the packages that currently import mtl. Thus we have to think about a route of transition and a package which can be installed in parallel to mtl is a first step, I think.
I also like to have a function 'state', which replaces the former 'State' constructor. I can also submit a patch if you want that.
You mean
state :: (s -> (a, s)) -> State s a state f = StateT (Identity . f)
and similarly for all the others? Sounds reasonable.
That's what I mean.