Re: subprogram must not be deeper than access type

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On Tue, 04 Oct 2011 06:26:01 +0200, Yannick Duchêne (Hibou57) wrote:

> Le Tue, 27 Sep 2011 09:52:09 +0200, Dmitry A. Kazakov  
> <mailbox@dmitry-kazakov.de> a écrit:
>> Compare it with declare-begin-end blocks they too have no names and have no
>> identifiable counterpart in the domain, just an implementation detail.
> Except these are just flowed. If you want a block to be possibly invoked  
> independently, then you make it a procedure, … which is named.

There is no clear margin, but the name of a procedure may refer to its name
and/or its singleton type. They are not separated properly, because Ada has
no procedural types.

BTW, blocks can be named in Ada:

A : begin
      null;
   end A;

Here A is the proper name, and you don't need the type of A. This type is
anonymous.

> If you do not need to access sub‑records of a record,

Access to the subrecord is needed, but only though its components not as a
whole. These components would be named but have anonymous types.

------------------------------
BTW, the list of parameters of a subprogram is an anonymous record type,
but Ada does not require its explicit declaration, e.g.

   type Integer_Tuple is record
      Left : Integer;
      Right : Integer;
   end record;
   function "+" : Integer_Tuple return Integer;

If it could, you would have so much longed variant arguments:

   type Printf_Arguments (Some_Discriminant : ...) is record
      case Some_Discriminant is
          when ... =>
          when ... =>
          ...
      end case;
   end record;
   pragma Unchecked_Union (Printf_Arguments);
   procedure Printf : Printf_Arguments;

(:-))

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