Re: Common ancestor (visibility rules)

[dmitry6243@my-deja.com]

In article <8bq726$lo8$1@nnrp1.deja.com>,
Robert Dewar <robert_dewar@my-deja.com> wrote:

> No need to invent a new name, it is called Standard
>
> Then package A could be specified as
> > Root.A and A's Foo as Root.A.Foo.

Yes, "Standard" was actually my first attempt, but I tried the
following (of course in the real program):
-------------------- b-a.adb
with Standard.A; use Standard.A;
separate (B)
procedure A is
begin
   Foo;
end A;

which does not work, because compiler do not understand withing of
Standard.A. This caused my confusion. The correct version is:
-------------------- b-a.adb
with A; use Standard.A;
separate (B)
procedure A is
begin
   Foo;
end A;

I must say, that the difference is rather subtle. I suppose it has some
relation with unit library management. Perhaps compiler should first
search for physical childs of Standard and then in case of failure,
discard the "Standard" prefix, so that:

with Standard.A; use Standard.A;

would be correct?

> > Interesting is that C++ has this
> > feature.
>
> Perhaps they copied it from Ada 95 :-)

Surely they did! (:-))

Regards,
Dmitry Kazakov


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