Linux Cubed Series 3: Developer Tools/Linux Cubed Series 3 - Developer Tools.iso/devel/lang/eiffel/smalleif.97/se.t/SmallEiffel/lib_std/boolean.e

Text File | 1996-05-02 | 1.5 KB | 77 lines

-- Part of SmallEiffel -- Read DISCLAIMER file -- Copyright (C)
-- Dominique COLNET and Suzanne COLLIN -- [e-mail]
--
expanded class BOOLEAN
--
-- Note : corresponding C type is "int"
--
inherit
   BOOLEAN_REF
      redefine
     infix "and", infix "and then", infix "or",
     infix "or else", infix "implies", infix "xor",
     prefix "not", to_string, to_integer
      end;

feature {ANY}

   infix "and" (other: BOOLEAN): BOOLEAN is
     -- `and' of Current with `other'.
      external "CSE"
      end;

   infix "and then" (other: BOOLEAN): BOOLEAN is
     -- Semi-strict `and' of Current with `other'.
      external "CSE"
      end;

   infix "implies"(other: BOOLEAN): BOOLEAN is
     -- Does Current imply `other'.
      external "CSE"
      end;

   infix "or" (other: BOOLEAN): BOOLEAN is
     -- `or' of Current with `other'
      external "CSE"
      end;

   infix "or else" (other: BOOLEAN): BOOLEAN is
     -- Semi-strict `or' of Current with `other'
      external "CSE"
      end;

   infix "xor" (other: BOOLEAN): BOOLEAN is
     -- `xor' of Current with `other'
      do
     if Current then
        Result := not other;
     else
        Result := other;
     end;
      end;

   prefix "not": BOOLEAN is
     -- `not' of Current.
      external "CSE"
      end;

   to_string: STRING is
      do
         if Current then
            Result := "true";
         else
            Result := "false";
         end;
      end;

   to_integer: INTEGER is
      do
     if Current then
        Result := 1;
     else
        Result := 0;
     end;
      end;

end -- BOOLEAN