On 14 October 2010 10:15, Jacek Generowicz
[Gregory: Sorry about duplicate, accidentally took it off-list.]
On 2010 Oct 14, at 09:46, Gregory Collins wrote: There is more information about the different ways of doing this kind of thing in Haskell in the OOHaskell paper: http://homepages.cwi.nl/~ralf/OOHaskell/
Abstract looks good. On the one hand I want to explore how Haskell allows me to do things in a way that doesn't resemble OO at all. On the other, it's good to see how OO-like things might be done in Haskell.
I find Section 2 in "Unfolding Abstract Datatypes" by Jeremy Gibbons a more pleasant example of existentials as its limited to abstract datatypes rather than fully blown OO (personally I don't particularly agree that the OO-Haskell style should be used more...) http://www.comlab.ox.ac.uk/jeremy.gibbons/publications/adt.pdf A typographical note, if you want to run the code in the paper /backwards E/ should be replaced with /forall/.