Re: Overriding puzzle

[gautier_niouzes@hotmail.com]

No, the "A'Class(o)" also makes the difference when type Custom is framed into a package:

with Ada.Text_IO; use Ada.Text_IO;

procedure Test_override is

  package Pkg is
    type A is tagged null record;

    procedure Header(o: A);
    procedure New_Page(o: A);

  end;

  package body Pkg is

    procedure Header(o: A) is
    pragma Unreferenced (o);
    begin
      Put_Line("This is a normal header");
    end;

    procedure New_Page(o: A) is
    begin
      Header(A'Class(o));
    end;
  end;

  package Pkg_cust is
    type Custom is new Pkg.A with null record;
    procedure Header(o: Custom);
  end;

  package body Pkg_cust is
    procedure Header(o: Custom) is
    pragma Unreferenced (o);
    begin
      Put_Line("This is a custom header");
    end;
  end;
    
  use Pkg_cust;
  
  obj: Custom;

begin
  New_Page(obj);
end;

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