Revamping the numeric classes

Dylan Thurston dpt@math.harvard.edu
Wed, 7 Feb 2001 16:54:50 -0500


On Wed, Feb 07, 2001 at 10:08:26PM +0000, andrew@andrewcooke.free-online.co.uk wrote:
> - even for me, no great mathematician, I found the forced inclusion of
> certain classes irritating (in my case - effectively implementing
> arithmetic on tuples - Enum made little sense and ordering is hacked
> in order to be total; why do I need to define either to overload "+"?)

Persumably you mean "quot" and "rem", since Enum is a superclass of
Integral, not Num.  toInteger must have been even worse, right?

> - what's the deal with fmap and map?

I think this one is historical:  map already existed before Haskell
was powerful enough to type fmap, and the decision was not to affect
existing programs too much.  Presumably Haskell 2 will have them
merged.

Best,
	Dylan Thurston