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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: Functions vs constants
Date: Thu, 24 Jul 2014 12:01:43 -0400
Organization: The World Public Access UNIX, Brookline, MA
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Date: 2014-07-24T12:01:43-04:00
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Victor Porton <porton@narod.ru> writes:

> It seems to me, that making constants functions (and so overloadable) would 
> not change meaning of any legal Ada program.

I think you can construct cases that are currently legal that would
become illegal with your proposed change.  How about this:

   procedure Overloaded(X: Integer);
   procedure Overloaded(X: Boolean);

   procedure P is
      X: constant Integer := 1;

      procedure Q is
         X: constant Boolean := True;
      begin
         Overloaded(X);
         ...

The above is legal, and calls the Boolean version of Overloaded.
If the X's overloaded each other, it would be ambiguous, and
therefore illegal.

Now, you might say the above SHOULD be illegal, and I'd agree.
But it's currently legal, and we shouldn't be breaking legal
programs.

> Thus, in my opinion, there is no reason to refuse this my proposal to make 
> constants functions (and so overloadable).

Another reason is implementation difficulty.  I suspect it might be
an earthquake for some implementations, so it might not be worth
the trouble -- not sufficiently broken.

- Bob