names, modules, types
Fergus Henderson
fjh@cs.mu.oz.au
Thu, 8 Feb 2001 22:59:44 +1100
On 07-Feb-2001, Marcin 'Qrczak' Kowalczyk <qrczak@knm.org.pl> wrote:
> So why is fmap separate now? Probably because having too much
> overloading causes ambiguities.
Perhaps. But I think there may be other reasons too.
Having fmap separate is useful for beginners and for teaching,
because you can describe `map' without having to talk about type classes.
Also, it is possible that the error messages that you get when you
make a mistake using `fmap' might be harder to understand.
The reasoning here is similar to the reasons that Haskell 98 has list
comprehensions rather than monad comprehensions.
--
Fergus Henderson <fjh@cs.mu.oz.au> | "I have always known that the pursuit
| of excellence is a lethal habit"
WWW: <http://www.cs.mu.oz.au/~fjh> | -- the last words of T. S. Garp.