21 May
2003
21 May
'03
12:23 p.m.
when you talk about a backtracking monad transformer which one are you refering to? ralf hinze seems to have a whole bunch of papers on the matter, some of which seem to be a lot like the "Maybe" transformer and some seem very complicated (but presumable are very efficient).
A simple one is this type CPS a ans = (a -> ans) -> ans newtype BacktrT m a = B (forall ans . CPS a (m ans -> m ans)) Cheers, Ralf