Ada 200Y

Ada 200Y

[Stephen Leake]

"amado.alves" <amado.alves@netcabo.pt> writes:

> Anyway, I'm ok with interfaces per se. I just worry that they might
> push other (for me more interesting) additions off the list (e.g.
> container library) given the scarse revision resources.

Hmm. Your objection to Java-style interfaces is that "you can do that
now in Ada". Well, clearly you can do "container libraries" now in
Ada. The only issue is to pick a standard one. 

Picking the Java-style interfaces as a standard way to do one flavor
of MI is easy to agree on. Picking a standard container library API
will be much harder, because there are so many more choices, and so
much less reason to pick one over another.

> /* Tangent but doubly related issue: increasing the power of
> generics viz. towards generic parameters would be also a more
> interesting addition to me. I mean to be able to pass a generic unit
> to a (mandatorily generic) unit. I came across many situations where
> this would be useful. */

I don't follow. How is this different from formal packages?

-- 
-- Stephe

RE: Ada 200Y

[amado.alves]

"Picking the Java-style interfaces as a standard way to do one flavor
of MI is easy to agree on."
Fake MI.
> /* Tangent but doubly related issue: increasing the power of
> generics viz. towards generic parameters would be also a more
> interesting addition to me. I mean to be able to pass a generic unit
> to a (mandatorily generic) unit. I came across many situations where
> this would be useful. */

I don't follow. How is this different from formal packages?
You can only pass instances as actuals for them. Instead I want to write for example
generic
  generic package Generic_Formal; -- Ada 2015
package P is
  type T is ...;

  package Instance is new Generic_Formal (T);
end;
generic
  ...
package G is
  ...
end;
package Instance_Of_P is new P (G);

Re: Ada 200Y

[Stephen Leake]

"amado.alves" <amado.alves@netcabo.pt> writes:

(please use a better quoting style, this was hard to sort out)

> stephen.leake@gsfc.nasa.gov writes:
> > "Picking the Java-style interfaces as a standard way to do one flavor
> > of MI is easy to agree on."

> Fake MI.

Hmm. No need to be nasty! I said "one flavor". I think we all agree
there are many ways to implement something that looks like multile
inheritance.

If you don't have a need for Java-style interfaces, fine; don't use
them! That doesn't mean the rest of us shouldn't get the chance to use
them.

> > > /* Tangent but doubly related issue: increasing the power of
> > > generics viz. towards generic parameters would be also a more
> > > interesting addition to me. I mean to be able to pass a generic unit
> > > to a (mandatorily generic) unit. I came across many situations where
> > > this would be useful. */
> > 
> > I don't follow. How is this different from formal packages?

> You can only pass instances as actuals for them. Instead I want to
> write for example 
> generic
>   generic package Generic_Formal; -- Ada 2015
> package P is
>   type T is ...;
> 
>   package Instance is new Generic_Formal (T);
> end;
> generic
>   ...
> package G is
>   ...
> end;
> package Instance_Of_P is new P (G);

Ah. I see. You can probably get a similar result for most cases now
with child generic packages; it would be interesting to see if that is
true in general.

-- 
-- Stephe