Re: bindings with Ada 2012 aspects

[Natasha Kerensikova <lithiumcat@gmail.com>]

Hello,

On 2012-04-26, Randy Brukardt <randy@rrsoftware.com> wrote:
> No language-defined aspects are allowed on renames, and the above is a 
> renames.
>
> The reason is that almost all language-defined aspects are the same for all 
> views of an entity, and a rename just introduces another view. Moreover, 
> this renames "trick" exists for pragmas simply to get around the limitations 
> of pragmas for overloaded entities, something that is totally unnecessary 
> for aspects.

I'm sorry to derail this thread a bit, but this interesting description
of renames makes we wonder even more why they are needed for public
subprograms implemented by generic instantiation. Like the following:

package Foo;

   procedure Bar (Arg_1 : in out Type_1; Arg_2 : in Type_2);

end Foo;

package body Foo

   generic
      type Formal_Type;
      with procedure Do_Stuff (Arg_2 : in Type_2);
   procedure Generic_Bar (Arg_1 : in out Formal_Type; Arg_2 : in Type_2);

   procedure Bar_Instance is new Generic_Bar (Type_1, Do_Real_Stuff);

   procedure Bar (Arg_1 : in out Type_1; Arg_2 : in Type_2)
      renames Bar_Instance;

end Foo;


What is so special about "just [introducing] another view" that cannot
be achieved by the more direct code below?

   procedure Bar is new Generic_Bar (Type_1, Do_Real_Stuff);



Thanks for your insights,
Natasha