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

Marcin 'Qrczak' Kowalczyk writes: [...]

My new record scheme proposal does not provide such lightweight extensibility, but fields can be added and deleted in a controlled way if the right types and instances are made.

Johan Nordlander must be on holiday or something, so I'll deputise for him. :-) O'Haskell also has add-a-field subtyping. Here's the coloured point example (from http://www.cs.chalmers.se/~nordland/ohaskell/survey.html): struct Point = x,y :: Float struct CPoint < Point = color :: Color Regards, Tom