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
_______________________________________________
Haskell mailing list
[EMAIL PROTECTED]
http://www.haskell.org/mailman/listinfo/haskell
