------------------------------------------------------------------------------
--                                                                          --
--                         GNAT RUN-TIME COMPONENTS                         --
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--                      S Y S T E M . W W D _ E N U M                       --
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------------------------------------------------------------------------------

--  This package contains routines used for Enumeration_Type'Wide_[Wide_]Width

with System.WCh_Con;

package System.WWd_Enum is
   pragma Pure;

   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.

   function Wide_Wide_Width_Enumeration_8
     (Names   : String;
      Indexes : System.Address;
      Lo, Hi  : Natural;
      EM      : System.WCh_Con.WC_Encoding_Method) return Natural;
   --  Same function for Wide_Wide_Width attribute

   function Wide_Wide_Width_Enumeration_16
     (Names   : String;
      Indexes : System.Address;
      Lo, Hi  : Natural;
      EM      : System.WCh_Con.WC_Encoding_Method) return Natural;
   --  Same function for Wide_Wide_Width attribute

   function Wide_Wide_Width_Enumeration_32
     (Names   : String;
      Indexes : System.Address;
      Lo, Hi  : Natural;
      EM      : System.WCh_Con.WC_Encoding_Method) return Natural;
   --  Same function for Wide_Wide_Width attribute

end System.WWd_Enum;