From mboxrd@z Thu Jan  1 00:00:00 1970
Path: eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail
From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: Renaming primitives.
Date: Wed, 10 Jan 2024 13:13:59 +0100
Organization: A noiseless patient Spider
Message-ID: <unm1m6$2ftcd$1@dont-email.me>
References: <unls1j$2f0up$3@dont-email.me>
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 8bit
Injection-Date: Wed, 10 Jan 2024 12:13:58 -0000 (UTC)
Injection-Info: dont-email.me; posting-host="3ec672b6e3be53c27e243d9bd8b20266";
	logging-data="2618765"; mail-complaints-to="abuse@eternal-september.org";	posting-account="U2FsdGVkX18ZGrQcQbOERYqi2Qrqdu95ODkhGmkftU4="
User-Agent: Mozilla Thunderbird
Cancel-Lock: sha1:1d1HNsPRF8B/1M1bATq/w1yOwLE=
Content-Language: en-US
In-Reply-To: <unls1j$2f0up$3@dont-email.me>
Xref: news.eternal-september.org comp.lang.ada:65979
List-Id: <comp.lang.ada>

On 2024-01-10 11:37, Blady wrote:

> Is a procedure renaming equivalent to a simple call?
> For instance:
>     procedure Log (Msg : String) is
>     begin
>        Ada.Text_IO.Put_Line (Msg);
>     end Log;
>     procedure My_Log_1 (Msg : String) is
>     begin
>        Log (Msg);
>     end My_Log_1;
>     procedure My_Log_2 (Msg : String) renames Log;
> 
> Almost, My_Log_1 is equivalent to My_Log_2, isn't it?
> 
> Is it the same with primitives?
> 
> For instance:
>     package Loggings is
>        type Logging is tagged record
>           Output : Ada.Text_IO.File_Access;
>        end record;
>        procedure Log (Handler : Logging; Msg : String);
>     end Loggings;
>     My_Handler : aliased Loggings.Logging := (Output => 
> Ada.Text_IO.Current_Output);
>     My_Generic_Handler : access Loggings.Logging'Class := 
> My_Handler'Access;
>     procedure My_Log_3 (Msg : String) renames My_Generic_Handler.Log;
> 
> To my surprise (well I hoped) My_Log_3 is compiled by GNAT.
> Is it conformed to the Ada standard?

This looks like a bug to me. ARM 8.5.4 (2/3) states that the right part 
of "renames" must be a name of a callable entity. My_Generic_Handler.Log 
is a procedure call which is not a callable entity name.

Renaming a callable result of a function call might be legal [and quite 
funny].

Disclaimer. I am not a language lawyer.

P.S. Specialization of subprograms would be a nice feature, though.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de