1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2008, Free Software Foundation, Inc. --
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. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 -- This package contains the lexical analyzer routines. This is used by the
27 -- compiler for scanning Ada source files.
29 with Casing
; use Casing
;
30 with Errout
; use Errout
;
32 with Style
; use Style
;
33 with Types
; use Types
;
37 procedure Initialize_Scanner
38 (Unit
: Unit_Number_Type
;
39 Index
: Source_File_Index
);
40 -- Initialize lexical scanner for scanning a new file. The caller has
41 -- completed the construction of the Units.Table entry for the specified
42 -- Unit and Index references the corresponding source file. A special
43 -- case is when Unit = No_Unit_Number, and Index corresponds to the
44 -- source index for reading the configuration pragma file.
46 function Determine_Token_Casing
return Casing_Type
;
47 -- Determines the casing style of the current token, which is
48 -- either a keyword or an identifier. See also package Casing.
50 procedure Obsolescent_Check
(S
: Source_Ptr
);
51 -- Called to handle pragma restrictions check for usage of obsolescent
52 -- character replacements during the scan.
54 procedure Set_Obsolescent_Check
(Value
: Boolean);
55 -- Activate or not obsolescent check
58 pragma Inline
(Post_Scan
);
59 -- Create nodes for tokens: Char_Literal, Identifier, Real_Literal,
60 -- Integer_Literal, String_Literal and Operator_Symbol.
62 procedure Scan_Reserved_Identifier
(Force_Msg
: Boolean);
63 -- This procedure is called to convert the current token, which the caller
64 -- has checked is for a reserved word, to an equivalent identifier. This is
65 -- of course only used in error situations where the parser can detect that
66 -- a reserved word is being used as an identifier. An appropriate error
67 -- message, pointing to the token, is also issued if either this is the
68 -- first occurrence of misuse of this identifier, or if Force_Msg is True.
74 -- The scanner used by the compiler is an instantiation of the
75 -- generic package Scng with routines appropriate to the compiler
77 package Scanner
is new Scng
78 (Post_Scan
=> Post_Scan
,
79 Error_Msg
=> Error_Msg
,
80 Error_Msg_S
=> Error_Msg_S
,
81 Error_Msg_SC
=> Error_Msg_SC
,
82 Error_Msg_SP
=> Error_Msg_SP
,
83 Obsolescent_Check
=> Obsolescent_Check
,
84 Style
=> Style
.Style_Inst
);
86 procedure Scan
renames Scanner
.Scan
;
87 -- Scan scans out the next token, and advances the scan state accordingly
88 -- (see package Scans for details). If the scan encounters an illegal
89 -- token, then an error message is issued pointing to the bad character,
90 -- and Scan returns a reasonable substitute token of some kind.