Revamping the numeric classes
Sat, 10 Feb 2001 16:52:39 +1100
On 08-Feb-2001, Marcin 'Qrczak' Kowalczyk <firstname.lastname@example.org> wrote:
> I don't like the idea of treating the case "no explicit definitions
> were given because all have default definitions which are OK"
> differently than "some explicit definitions were given".
I don't really like it that much either, but...
> When there is a superclass, it must have an instance defined, so if
> we permit such thing at all, I would let it implicitly define all
> superclass instances not defined explicitly, or something like that.
> At least when all methods have default definitions. Yes, I know that
> they can be mutually recursive and thus all will be bottoms...
... that is the problem I was trying to solve.
> So maybe there should be a way to specify that default definitions
> are cyclic and some of them must be defined?
I agree 100%.
> It is usually written in comments anyway, because it is not immediately
> visible in the definitions.
Yes. Much better to make it part of the language, so that the compiler
can check it.
> (now any method definition
> can be omitted even if it has no default!),
Yeah, that one really sucks.
Fergus Henderson <email@example.com> | "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.