deriving

[Mark Carroll]

On Tue, 21 Aug 2001, Tom Pledger wrote:
(snip)
>     http://research.microsoft.com/Users/simonpj/Papers/derive.htm

Aha, thank you very much. This explains a lot - I had assumed that Haskell
must already have had something of the sort that nobody had told me about,
but apparently not! I again tripped over my assumptions. (-: So, as
Haskell 98 stands, you _can't_ make your own type classes that types can
'derive' from. It is interesting to see the extensions that people have
been proposing - I wonder what the next version of Haskell will look like,
and when. (-:

-- Mark