Neil Mitchell wrote:
Hi
If we're going to have a strict StateT then it would make sense to have a strict State too. Control.Monad.State.Strict perhaps? (and likewise for the other mtl monads, where appropriate).
For foldl we have foldl and foldl'. Why not State and State' ? I'm not a particular fan of changing the imports to get different sets of behaviours...
So if you want (gasp!) strictness you have to pay the Prime Tax :-) I'm not keen on having a bias implied by the naming convention: State' suggests that this is a special/modified version of State, whereas I think both versions are equally useful. Using lazy when you wanted strict can result in a space leak, using strict when you wanted lazy can result in a stack overflow or a time leak. I don't mind so much a bias in the module names: e.g. Control.Monad.State could be the lazy version, Control.Monad.State.Strict the strict version, that's much less intrusive. Cheers, Simon