------------------------------------------------------------------------------
--                                                                          --
--                         GNAT RUN-TIME COMPONENTS                         --
--                                                                          --
--                      S Y S T E M . W W D _ E N U M                       --
--                                                                          --
--                                 S p e c                                  --
--                                                                          --
--          Copyright (C) 1992-2000 Free Software Foundation, Inc.          --
--                                                                          --
-- GNAT is free software;  you can  redistribute it  and/or modify it under --
-- terms of the  GNU General Public License as published  by the Free Soft- --
-- ware  Foundation;  either version 2,  or (at your option) any later ver- --
-- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT 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 --
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-- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
-- MA 02111-1307, USA.                                                      --
--                                                                          --
-- As a special exception,  if other files  instantiate  generics from this --
-- unit, or you link  this unit with other files  to produce an executable, --
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-- covered  by the  GNU  General  Public  License.  This exception does not --
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-- covered by the  GNU Public License.                                      --
--                                                                          --
-- GNAT was originally developed  by the GNAT team at  New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc.      --
--                                                                          --
------------------------------------------------------------------------------

--  This package contains the routine used for Enumeration_Type'Wide_Width

with System.WCh_Con;

package System.WWd_Enum is
pragma Pure (WWd_Enum);

   function Wide_Width_Enumeration_8
     (Names   : String;
      Indexes : System.Address;
      Lo, Hi  : Natural;
      EM      : System.WCh_Con.WC_Encoding_Method)
      return    Natural;
   --  Used to compute Enum'Wide_Width where Enum is an enumeration subtype
   --  other than those defined in package Standard. Names is a string with
   --  a lower bound of 1 containing the characters of all the enumeration
   --  literals concatenated together in sequence. Indexes is the address
   --  of an array of type array (0 .. N) of Natural_8, where N is the
   --  number of enumeration literals in the type. The Indexes values are
   --  the starting subscript of each enumeration literal, indexed by Pos
   --  values, with an extra entry at the end containing Names'Length + 1.
   --  The reason that Indexes is passed by address is that the actual type
   --  is created on the fly by the expander.
   --
   --  Lo and Hi are the Pos values of the lower and upper bounds of the
   --  subtype. The result is the value of Width, i.e. the maximum value
   --  of the length of any enumeration literal in the given range. The
   --  fifth parameter, EM, is the wide character encoding method used in
   --  the Names table.

   function Wide_Width_Enumeration_16
     (Names   : String;
      Indexes : System.Address;
      Lo, Hi  : Natural;
      EM      : System.WCh_Con.WC_Encoding_Method)
      return    Natural;
   --  Identical to Wide_Width_Enumeration_8 except that it handles types
   --  using array (0 .. Num) of Natural_16 for the Indexes table.

   function Wide_Width_Enumeration_32
     (Names   : String;
      Indexes : System.Address;
      Lo, Hi  : Natural;
      EM      : System.WCh_Con.WC_Encoding_Method)
      return    Natural;
   --  Identical to Wide_Width_Enumeration_8 except that it handles types
   --  using array (0 .. Num) of Natural_32 for the Indexes table.

end System.WWd_Enum;
