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From: Blady
Newsgroups: comp.lang.ada
Subject: Re: Renaming primitives.
Date: Thu, 11 Jan 2024 11:09:38 +0100
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Le 11/01/2024 à 03:18, Randy Brukardt a écrit :
> "Blady" wrote in message
> news:unls1j$2f0up$3@dont-email.me...
>> Is a procedure renaming equivalent to a simple call?
>
> General point: "Equivalent" is never true in programming language design. If
> construct A is equivalent in every way to construct B, then they have to be
> the same construct.
>
> For instance, in your example below, the two subprogram declarations have
> different identifiers which have different visibility (two declarations
> cannot be at exactly the same place), so there is at least one way that
> they're not equivalent.
>
> So, if you want to talk about "equivalence", you need to qualify that by
> what properties you are interested in.
Well, I hadn't find a better word :-(
> ...
>> What is happening if My_Generic_Handler change?
>
> Nothing. The names in a renaming are evaluated when the renaming is
> declared. If there are parts that could change, the compiler has to save the
> values at the point of the renaming. That's true for all forms of renaming
> (some names, like package names, can't change meaning so the example isn't
> possible, of course).
Yet, the code:
My_Log_3 ("Hei");
My_Generic_Handler := My_Full_Handler'Access;
My_Log_3 ("Hei");
gives:
Hei
Full Hei
I thought that was correct, wasn't it?
GNAT issue ?
> ...
>> I got:
>> test_20240110_renproc.adb:47:14: error: too many arguments in call to
>> "log"
>>
>> Is it a correct or a GNAT issue?
>
> Looks like a bug to me. Not too surprising, though, this sort of thing is a
> special case in a compiler and often added to pass an ACATS test or user bug
> report. Such fixes can often not be fully general.
Thanks, I'll report it.
Pascal.