Are anonymous type classes the right model at all? (replying to Re: Are fundeps the right model at all?)

John Meacham
Fri, 29 Dec 2000 00:37:45 -0800

I also like the approach of generalizing the record system, although I
have not evaluated your particular proposal. Speaking of record
improvements why is
not listed on the future of haskell page? has it already been determined
to not be in the future of haskell or has no one gotten around to it?
Does anyone else read this proposal and drool? 

Speaking of this proposal does anyone else see parallels between the
lightweight modules proposal and the implicit parameters proposal as implemented in ghc.

in particular implicit parameters seem like they would be able to be
implemented as syntatic sugar on the lightweight module system,

one could rewrite implicit parameters as every function taking a record
which we can call 'imp' now '?foo' can be rewritten as '' and the
'with ?foo = 1' construct can be rewritten as nimp = {imp | foo := 1}
and then passing nimp to all called functions. I have not thought this
too far thorough so I could be missing something obvious but I think it
shows potential at least for the unification of two popular extensions. 

and I am pretty sure this was too obvious to mention in the lightweight
records paper but the section of (.foo) being equivalent to 
(\{_|foo=v} -> v) seems appropriate.


John Meacham
California Institute of Technology, Alum.