Henrik Nilsson <[EMAIL PROTECTED]> writes: > Dear all, > > John Mecham wrote: > >> Yeah, I have been coming to the same conclusion myself. it pains me a >> lot. (monad transformers! I need thee!) but its not like fundeps will >> go away, they will just still be experimental so it isn't the end of >> the world. > > But isn't the whole point of Haskell' to standardise those features > that are agreed to be necessary for writing real-world > applications and libraries in a reasonable way? > > My concern is not that I fear not being able to compile my programs > after Haskell' is done. I'm worried about too much code not being > Haskell' compliant in the end, and, worse, too many people deciding > that they still have to rely on extensions beyond Haskell' for writing > "real" applications and libraries.
I am very concerned about this as well. In most of my production code, I avoid extensions, but MPTC and functional dependencies are two that I have not been able to avoid. Any time I use the class system, I use MPTC, anytime I use MPTC, I use fundeps. The trouble with "blessing" fundeps is that they might not pan out in the end, and it would be a shame to add them to Haskell' and then remove them again for Haskell'' (if there were such a thing) in favor of associated types, for instance. How do we solve this dilemma? Some proposals that have come up: - Simon has proposed that we examine a limited version of functional dependencies. - Another option, though a scary one at this point, is to look closely at associated types. - Another option is to punt; we declare them as an extension and figure out a way to "bless" extensions (beyond Cabal, I guess). - Any others? Can someone put together a wiki page these choices with trade-offs? Ravi, Manuel? peace, isaac _______________________________________________ Haskell-prime mailing list [email protected] http://haskell.org/mailman/listinfo/haskell-prime
