[Aldor-l] [Aldor-combinat-devel] Set

[Martin Rubey]

"Christian Aistleitner" <tmgisi at gmx.at> writes:


> > Well, it seem that I have to implement my own SetSpecies. :-(
> 
> Yes. But is SetSpecies a set keeping the order of its elements? Then give  
> it a “descriptive name”, so other people can use it as well.

Maybe the right name would be "OrderedSet". In Axiom that's a category, I'm not
sure whether it's OK to have a category and a domain having the same name. I
believe it should be, though. I think it's quite clear that the names refer to
different things.

>  From my feeling, an “any instance of” should be perfectly possible with the
> current Aldor language. Currently, you can model
> 
>    ( l: any instance of ListType T )
> 
> by
> 
>    ( LT: ListType T, l: LT )
> 
> . “any instance of” would just allow you to eliminate the first parameter.
> It would make code more compact and more readable without losing its
> expressivness.  (Of course we would also need an operator allowing to obtain
> the current value of “any instance of ListType T”.)

Yes, I agree. I very often run into situations like that, and since Axiom
doesn't support dependend types, it is even more difficult to come up with
something proper...


Martin