Re: Will "renames" increase program size?

["Yannick Duchêne (Hibou57)" <yannick_duchene@yahoo.fr>]

Le Sat, 18 Jun 2011 09:54:29 +0200, Dmitry A. Kazakov  
<mailbox@dmitry-kazakov.de> a écrit:
> Does this copy? It seems that according to you, you cannot tell without
> looking into the body of Foo:
>
>    function Foo return T is -- This copies
>       Result : T;
>    begin
>       return T;
>    end Foo;
>
>    function Foo return T is -- This does not copy
>    begin
>       return Result : T;
>    end Foo;

May be I did not really understood what you meant, but a simple test  
program shows this makes no difference:


    -- Begin Test.adb  
------------------------------------------------------------

    with Ada.Text_IO;

    procedure Test is

       Foo_1_Seed : Integer := 0;

       function Foo_1 return Integer
       is
          Result : constant Integer := Foo_1_Seed;
       begin
          Foo_1_Seed := Foo_1_Seed + 1;
          return Result;
       end;

       Foo_2_Seed : Integer := 0;

       function Foo_2 return Integer is
       begin
          return Result : constant Integer := Foo_2_Seed do
             Foo_2_Seed := Foo_2_Seed + 1;
          end return;
       end;

       Foo_1_1 : Integer renames Foo_1;
       Foo_1_2 : Integer renames Foo_1;
       Foo_1_3 : Integer renames Foo_1;

       Foo_2_1 : Integer renames Foo_2;
       Foo_2_2 : Integer renames Foo_2;
       Foo_2_3 : Integer renames Foo_2;

       procedure Put (Label : in String; Value : in Integer) is
          package Text_IO renames Ada.Text_IO;
          package Integer_IO is new Ada.Text_IO.Integer_IO (Integer);
       begin
          Text_IO.Put (Label);
          Text_IO.Put (" is ");
          Integer_IO.Put (Value);
          Text_IO.New_Line;
       end;

    begin

       Put (Label => "Foo_1_1", Value => Foo_1_1);
       Put (Label => "Foo_1_2", Value => Foo_1_2);
       Put (Label => "Foo_1_3", Value => Foo_1_3);

       Put (Label => "Foo_2_1", Value => Foo_2_1);
       Put (Label => "Foo_2_2", Value => Foo_2_2);
       Put (Label => "Foo_2_3", Value => Foo_2_3);

    end Test;

    -- End of Test.adb  
-----------------------------------------------------------

And the output:

    -- Begin Output ------

    Foo_1_1 is           0
    Foo_1_2 is           1
    Foo_1_3 is           2
    Foo_2_1 is           0
    Foo_2_2 is           1
    Foo_2_3 is           2

    -- End of Output -----

-- 
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