| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT COMPILER COMPONENTS -- |
| -- -- |
| -- S Y S T E M . V A L _ W C H A R -- |
| -- -- |
| -- B o d y -- |
| -- -- |
| -- $Revision: 1.2 $ -- |
| -- -- |
| -- Copyright (C) 1992-1997, 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 -- |
| -- Public License distributed with GNAT; see file COPYING. If not, write -- |
| -- 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, -- |
| -- this unit does not by itself cause the resulting executable to be -- |
| -- covered by the GNU General Public License. This exception does not -- |
| -- however invalidate any other reasons why the executable file might be -- |
| -- covered by the GNU Public License. -- |
| -- -- |
| -- GNAT was originally developed by the GNAT team at New York University. -- |
| -- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| with System.Val_Util; use System.Val_Util; |
| with System.WCh_Con; use System.WCh_Con; |
| with System.WCh_StW; use System.WCh_StW; |
| |
| package body System.Val_WChar is |
| |
| -------------------------- |
| -- Value_Wide_Character -- |
| -------------------------- |
| |
| function Value_Wide_Character |
| (Str : String; |
| EM : WC_Encoding_Method) |
| return Wide_Character |
| is |
| F : Natural; |
| L : Natural; |
| S : String (Str'Range) := Str; |
| |
| begin |
| Normalize_String (S, F, L); |
| |
| -- Character literal case |
| |
| if S (F) = ''' and then S (L) = ''' then |
| |
| -- If just three characters, simple character case |
| |
| if L - F = 2 then |
| return Wide_Character'Val (Character'Pos (S (F + 1))); |
| |
| -- Otherwise must be a wide character in quotes. The easiest |
| -- thing is to convert the string to a wide string and then |
| -- pick up the single character that it should contain. |
| |
| else |
| declare |
| WS : constant Wide_String := |
| String_To_Wide_String (S (F + 1 .. L - 1), EM); |
| |
| begin |
| if WS'Length /= 1 then |
| raise Constraint_Error; |
| |
| else |
| return WS (WS'First); |
| end if; |
| end; |
| end if; |
| |
| -- the last two values of the type have language-defined names: |
| |
| elsif S = "FFFE" then |
| return Wide_Character'Val (16#FFFE#); |
| |
| elsif S = "FFFF" then |
| return Wide_Character'Val (16#FFFF#); |
| |
| -- Otherwise must be a control character |
| |
| else |
| for C in Character'Val (16#00#) .. Character'Val (16#1F#) loop |
| if S (F .. L) = Character'Image (C) then |
| return Wide_Character'Val (Character'Pos (C)); |
| end if; |
| end loop; |
| |
| for C in Character'Val (16#7F#) .. Character'Val (16#9F#) loop |
| if S (F .. L) = Character'Image (C) then |
| return Wide_Character'Val (Character'Pos (C)); |
| end if; |
| end loop; |
| |
| raise Constraint_Error; |
| end if; |
| |
| end Value_Wide_Character; |
| |
| end System.Val_WChar; |
