------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- W I D E C H A R -- -- -- -- S p e c -- -- -- -- Copyright (C) 1992-2009 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 3, 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. -- -- -- -- As a special exception under Section 7 of GPL version 3, you are granted -- -- additional permissions described in the GCC Runtime Library Exception, -- -- version 3.1, as published by the Free Software Foundation. -- -- -- -- You should have received a copy of the GNU General Public License and -- -- a copy of the GCC Runtime Library Exception along with this program; -- -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- -- . -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ -- Subprograms for manipulation of wide character sequences. Note that in -- this package, wide character and wide wide character are not distinguished -- since this package is basically concerned with syntactic notions, and it -- deals with Char_Code values, rather than values of actual Ada types. with Types; use Types; package Widechar is Wide_Char_Byte_Count : Nat := 0; -- This value is incremented whenever Scan_Wide or Skip_Wide is called. -- The amount added is the length of the wide character sequence minus -- one. This means that the count that accumulates here represents the -- difference between the length in characters and the length in bytes. -- This is used for checking the line length in characters. function Length_Wide return Nat; -- Returns the maximum length in characters for the escape sequence that -- is used to encode wide character literals outside the ASCII range. Used -- only in the implementation of the attribute Width for Wide_Character -- and Wide_Wide_Character. procedure Scan_Wide (S : Source_Buffer_Ptr; P : in out Source_Ptr; C : out Char_Code; Err : out Boolean); -- On entry S (P) points to the first character in the source text for -- a wide character (i.e. to an ESC character, a left bracket, or an -- upper half character, depending on the representation method). A -- single wide character is scanned. If no error is found, the value -- stored in C is the code for this wide character, P is updated past -- the sequence and Err is set to False. If an error is found, then -- P points to the improper character, C is undefined, and Err is -- set to True. procedure Set_Wide (C : Char_Code; S : in out String; P : in out Natural); -- The escape sequence (including any leading ESC character) for the -- given character code is stored starting at S (P + 1), and on return -- P points to the last stored character (i.e. P is the count of stored -- characters on entry and exit, and the escape sequence is appended to -- the end of the stored string). The character code C represents a code -- originally constructed by Scan_Wide, so it is known to be in a range -- that is appropriate for the encoding method in use. procedure Skip_Wide (S : String; P : in out Natural); -- On entry, S (P) points to an ESC character for a wide character escape -- sequence or to an upper half character if the encoding method uses the -- upper bit, or to a left bracket if the brackets encoding method is in -- use. On exit, P is bumped past the wide character sequence. No error -- checking is done, since this is only used on escape sequences generated -- by Set_Wide, which are known to be correct. procedure Skip_Wide (S : Source_Buffer_Ptr; P : in out Source_Ptr); -- Similar to the above procedure, but operates on a source buffer -- instead of a string, with P being a Source_Ptr referencing the -- contents of the source buffer. function Is_Start_Of_Wide_Char (S : Source_Buffer_Ptr; P : Source_Ptr) return Boolean; -- Determines if S (P) is the start of a wide character sequence end Widechar;