On 11/08/10 07:51, Christian Maeder wrote: > I still favor parsec 2 over parsec 3 because > > a) parsec 3 is no longer haskell98 (as major parts of parsec 2 are)
I can't find my notes (might've disappeared in a system crash), but I went through all the HP packages, and I think each of the extensions that parsec 3 uses was used in some place in some other Platform package(s) too (even after excluding obviously nonportable things like template-haskell and the GHC-specific part of 'array'). And not all of parsec 2 is haskell98 (its cabal file mentions ExistentialQuantification and PolymorphicComponents). In addition to parsec 2's extensions, parsec 3 uses MultiParamTypeClasses, FlexibleInstances, FlexibleContexts, DeriveDataTypeable. I guess the first three of those are pretty tame (?) (or at least they seem to be used in miscellaneous places..). And DeriveDataTypeable is used by extensible-exceptions, which is a rather central library (whether you get it from 'base' or 'extensible-exceptions', either way). > I think the maintainers of "parsec 3" should create new package > "parsec3" without the compatibility layer. A new package parsec2 was > already created. That's an idea/vision that I think hasn't been brought up before (I might have forgot), in all our discussions of Parsec -- to make new names for both parsec2 and parsec3, and drop the compatibility layer in parsec3. (AFAIK there's rarely a reason to share parser data-types widely between modules / in interfaces, which in other cases makes a major benefit for having compatibility-layers and not just two separate library versions.) -Isaac _______________________________________________ Haskell-platform mailing list Haskell-platform@projects.haskell.org http://projects.haskell.org/cgi-bin/mailman/listinfo/haskell-platform
