-- This file is  free  software, which  comes  along  with  SmallEiffel. This
-- software  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. You can modify it as you want, provided
-- this header is kept unaltered, and a notification of the changes is added.
-- You  are  allowed  to  redistribute  it and sell it, alone or as a part of 
-- another product.
--          Copyright (C) 1994-98 LORIA - UHP - CRIN - INRIA - FRANCE
--            Dominique COLNET and Suzanne COLLIN - colnet@loria.fr 
--                       http://www.loria.fr/SmallEiffel
--
class INTEGER_REF

inherit
   NUMERIC
      undefine out_in_tagged_out_memory, fill_tagged_out_memory
      redefine
	 infix "^", prefix "-", prefix "+"
      end;
   COMPARABLE
      redefine compare, out_in_tagged_out_memory, 
	 fill_tagged_out_memory
      end;
   
creation make
   
feature 

   item: INTEGER;
   
   make(value: INTEGER) is
      do
	 item := value
      end;
   
feature
   
   set_item(value: like item) is
      do
	 item := value;
      end;

   infix "+" (other: like Current): like Current is
      do
	 !!Result.make (item + other.item)
      end;
   
   infix "-" (other: like Current): like Current is
      do
	 !!Result.make (item - other.item)
      end;

   infix "*" (other: like Current): like Current is
      do
	 !!Result.make (item * other.item)
      end;

   infix "/" (other: like Current): DOUBLE_REF is
      do
	 !!Result.make (item / other.item)
      end;

   infix "//" (other: like Current): like Current is
	 -- Integer division by `other'.
      require
	 divisible (other)
      do
	 !!Result.make (item // other.item)
      end;

   infix "\\" (other: like Current): like Current is
	 -- Remainder of integer division by `other'.
      require
	 valid_modulus: divisible (other)
      do
	 !!Result.make (item \\ other.item)
      end;

   infix "^" (exp: INTEGER): like Current is
      do
	 !!Result.make (item ^ exp)
      end;

   infix "<" (other: like Current): BOOLEAN is
      do
	 Result := (item < other.item)
      end;

   prefix "+": like Current is
      do
	 !!Result.make (item)
      end;

   prefix "-": like Current is
      do
	 !!Result.make (-item)
      end;

   compare (other: like Current): INTEGER is
      do
	 Result := item - other.item
      end;

   divisible(other: like Current): BOOLEAN is
      do
	 Result := (other.item /= 0)
      end;

   one: like Current is
      do
	 !!Result.make (1)
      end;

   zero: like Current is
      do
	 !!Result.make (0)
      end;

   out_in_tagged_out_memory, fill_tagged_out_memory is
      do
	 item.fill_tagged_out_memory;
      end;

   hash_code: INTEGER is
      do
	 Result := item.hash_code;
      end;

end -- INTEGER_REF