Re: Abstract Functions

["Marin David Condic" <marin.condic.auntie.spam@pacemicro.com>]

That is one possible way to go. However, what I have is a working parent
type that does useful things in its own right. It would be useful to have a
way of keeping it executable, but adding one or more operations that would
require extension. Basically, if you have a type that is a few generations
down the inheritance tree and now want to add some abstract operations, the
only way to do that is make the whole tree of types abstract. I'd prefer not
to do that.

Its the sort of thing where I've gone down a chain of inheritance and said
"O.K. Now I need the user to provide me with some functions and I don't want
to make this generic." I suppose I could use pointers to functions but I've
never liked that answer.

A question I could get answered by the compiler, but maybe this is less
typing: Can I have an abstract tagged type that has data fields? My
recollection of examples I've seen have not had data - just null records.

MDC
--
Marin David Condic
Senior Software Engineer
Pace Micro Technology Americas    www.pacemicro.com
Enabling the digital revolution
e-Mail:    marin.condic@pacemicro.com
Web:      http://www.mcondic.com/


"Ted Dennison" <dennison@telepath.com> wrote in message
news:6b_27.15423$Kf3.181711@www.newsranger.com...
> In article <9ihnia$i8h$1@nh.pace.co.uk>, Marin David Condic says...
> >
>
> I believe you can have non-abstract primitive subprograms for abstract
types.
> What's wrong with doing that?