1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT COMPILER COMPONENTS                         --
4--                                                                          --
5--                                C S E T S                                 --
6--                                                                          --
7--                                 S p e c                                  --
8--                                                                          --
9--          Copyright (C) 1992-2013, Free Software Foundation, Inc.         --
10--                                                                          --
11-- GNAT is free software;  you can  redistribute it  and/or modify it under --
12-- terms of the  GNU General Public License as published  by the Free Soft- --
13-- ware  Foundation;  either version 3,  or (at your option) any later ver- --
14-- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
15-- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
16-- or FITNESS FOR A PARTICULAR PURPOSE.                                     --
17--                                                                          --
18-- As a special exception under Section 7 of GPL version 3, you are granted --
19-- additional permissions described in the GCC Runtime Library Exception,   --
20-- version 3.1, as published by the Free Software Foundation.               --
21--                                                                          --
22-- You should have received a copy of the GNU General Public License and    --
23-- a copy of the GCC Runtime Library Exception along with this program;     --
24-- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
25-- <http://www.gnu.org/licenses/>.                                          --
26--                                                                          --
27-- GNAT was originally developed  by the GNAT team at  New York University. --
28-- Extensive contributions were provided by Ada Core Technologies Inc.      --
29--                                                                          --
30------------------------------------------------------------------------------
31
32package Csets is
33   pragma Elaborate_Body;
34
35   --  This package contains character tables for the various character
36   --  sets that are supported for source representation. Character and
37   --  string literals are not affected, only identifiers. For each set,
38   --  the table in this package gives the mapping of letters to their
39   --  upper case equivalent. Each table thus provides the information
40   --  for building the table used to fold lower case to upper case, and
41   --  also the table of flags showing which characters are allowed in
42   --  identifiers.
43
44   type Translate_Table is array (Character) of Character;
45   --  Type used to describe translate tables
46
47   type Char_Array_Flags is array (Character) of Boolean;
48   --  Type used for character attribute arrays. Note that we deliberately
49   --  do NOT pack this table, since we don't want the extra overhead of
50   --  accessing a packed bit string.
51
52   ----------------------------------------------
53   -- Character Tables For Current Compilation --
54   ----------------------------------------------
55
56   procedure Initialize;
57   --  Routine to initialize following character tables, whose content depends
58   --  on the character code being used to represent the source program. In
59   --  particular, the use of the upper half of the 8-bit code set varies.
60   --  The character set in use is specified by the value stored in
61   --  Opt.Identifier_Character_Set, which has the following settings:
62
63   --    '1'  Latin-1  (ISO-8859-1)
64   --    '2'  Latin-2  (ISO-8859-2)
65   --    '3'  Latin-3  (ISO-8859-3)
66   --    '4'  Latin-4  (ISO-8859-4)
67   --    '5'  Cyrillic (ISO-8859-5)
68   --    'p'  IBM PC   (code page 437)
69   --    '8'  IBM PC   (code page 850)
70   --    '9'  Latin-9  (ISO-8859-15)
71   --    'f'  Full upper set (all distinct)
72   --    'n'  No upper characters (Ada/83 rules)
73   --    'w'  Latin-1 plus wide characters also allowed
74
75   function Is_Upper_Case_Letter (C : Character) return Boolean;
76   pragma Inline (Is_Upper_Case_Letter);
77   --  Determine if character is upper case letter
78
79   function Is_Lower_Case_Letter (C : Character) return Boolean;
80   pragma Inline (Is_Lower_Case_Letter);
81   --  Determine if character is lower case letter
82
83   Fold_Upper : Translate_Table;
84   --  Table to fold lower case identifier letters to upper case
85
86   Fold_Lower : Translate_Table;
87   --  Table to fold upper case identifier letters to lower case
88
89   Identifier_Char : Char_Array_Flags;
90   --  This table has True entries for all characters that can legally appear
91   --  in identifiers, including digits, the underline character, all letters
92   --  including upper and lower case and extended letters (as controlled by
93   --  the setting of Opt.Identifier_Character_Set), left bracket for brackets
94   --  notation wide characters and also ESC if wide characters are permitted
95   --  in identifiers using escape sequences starting with ESC.
96
97end Csets;
98