-- Copyright 2012-2015 Free Software Foundation, Inc. -- -- This program is free software; you can redistribute it and/or modify -- it under the terms of the GNU General Public License as published by -- the Free Software Foundation; either version 3 of the License, or -- (at your option) any later version. -- -- This program is distributed in the hope that it will be useful, -- but WITHOUT ANY WARRANTY; without even the implied warranty of -- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -- GNU General Public License for more details. -- -- You should have received a copy of the GNU General Public License -- along with this program. If not, see . package Classes is type Point is record X : Integer; Y : Integer; end record; type Shape is abstract tagged null record; type Shape_Access is access all Shape'Class; type Drawable is interface; type Drawable_Access is access all Drawable'Class; procedure Draw (D : Drawable) is abstract; type Circle is new Shape and Drawable with record Center : Point; Radius : Natural; end record; procedure Draw (R : Circle); My_Circle : Circle := ((1, 2), 3); My_Shape : Shape'Class := Shape'Class (My_Circle); My_Drawable : Drawable'Class := Drawable'Class (My_Circle); S_Access : Shape_Access := new Circle'(My_Circle); D_Access : Drawable_Access := new Circle'(My_Circle); type R (MS : Shape_Access; MD : Drawable_Access) is record E : Integer; end record; MR : R := (MS => S_Access, MD => D_Access, E => 42); type Shape_Array is array (1 .. 4) of Shape_Access; type Drawable_Array is array (1 .. 4) of Drawable_Access; S_Array : Shape_Array := (others => S_Access); D_Array : Drawable_Array := (others => D_Access); end Classes;