Re: Problem with instantiating generic procedure

[Robert Dewar <robert_dewar@my-deja.com>]

In article <m3so6mdw05.fsf@deneb.cygnus.stuttgart.netsurf.de>,
  Florian Weimer <fw@s.netic.de> wrote:
> From my limited point of view, I don't see it either.
>
> There's a related thing I'd like to see improved in a future
Ada
> revision: pragma Import requires the use of renaming
declarations as
> well if the Ada functions in question are overloaded.  The
effects are
> quite similar here (namespace pollution).

But the name space pollution is a minimal problem, because it
occurs only in private parts or in package bodies, not in
package specs.

We did discuss the possibility of completing subprogram
declarations with generic instantiations, but it was considered
too much machinery for too little gain.

Remember this is just syntactic sugar for defining a body which
does the instantiation internally and then calls the procedure.
In practice, this is the way it would be implemented in any
case.

I would guess this is in practice of minimal importance. In all
the use of GNAT so far, this issue has never come up, so it is
certainly not something that many people expect to be there!

As for pragma Import, the renaminings can all be done in the
private part, so this is not really a burden:

package p is
   procedure q;
   procedure q (x : integer);
private
   procedure q_no_args renames q;
   procedure q_int_arg (x : integer) renames q;

   pragma Import (C, q_no_args);
   pragma Import (C, q_int_arg);

end p;

Indeed, since you need separate names for the routines that
implement these two cases, forcing names to be used in this
way can actually make things clearer!

>


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