1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2003 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 2, 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 COPYING. If not, write --
19 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
20 -- MA 02111-1307, USA. --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
25 ------------------------------------------------------------------------------
27 -- This package contains a generic lexical analyzer. This is used
28 -- for scanning Ada source files or text files with an Ada-like syntax,
29 -- such as project files. It is instantiated in Scn and Prj.Err.
31 with Casing; use Casing;
33 with Types; use Types;
36 with procedure Post_Scan;
37 -- Procedure called by Scan for the following tokens:
38 -- Tok_Char_Literal, Tok_Identifier, Tok_Real_Literal, Tok_Real_Literal,
39 -- Tok_Integer_Literal, Tok_String_Literal, Tok_Operator_Symbol.
41 with procedure Error_Msg (Msg : String; Flag_Location : Source_Ptr);
42 -- Output a message at specified location
44 with procedure Error_Msg_S (Msg : String);
45 -- Output a message at current scan pointer location
47 with procedure Error_Msg_SC (Msg : String);
48 -- Output a message at the start of the current token
50 with procedure Error_Msg_SP (Msg : String);
51 -- Output a message at the start of the previous token
53 with package Style is new Styleg
54 (Error_Msg, Error_Msg_S, Error_Msg_SC, Error_Msg_SP);
55 -- Instantiation of Styleg with the same error reporting routines
59 procedure Initialize_Scanner
60 (Unit : Unit_Number_Type;
61 Index : Source_File_Index);
62 -- Initialize lexical scanner for scanning a new file. The caller has
63 -- completed the construction of the Units.Table entry for the specified
64 -- Unit and Index references the corresponding source file. A special
65 -- case is when Unit = No_Unit_Number, and Index corresponds to the
66 -- source index for reading the configuration pragma file.
67 -- Initialize_Scanner does not call Scan.
70 -- Scan scans out the next token, and advances the scan state accordingly
71 -- (see package Scan_State for details). If the scan encounters an illegal
72 -- token, then an error message is issued pointing to the bad character,
73 -- and Scan returns a reasonable substitute token of some kind.
74 -- For tokens Char_Literal, Identifier, Real_Literal, Integer_Literal,
75 -- String_Literal and Operator_Symbol, Post_Scan is called after scanning.
77 function Determine_Token_Casing return Casing_Type;
78 pragma Inline (Determine_Token_Casing);
79 -- Determines the casing style of the current token, which is
80 -- either a keyword or an identifier. See also package Casing.
82 procedure Set_Special_Character (C : Character);
83 -- Indicate that one of the following character '#', '$', '?', '@', '`',
84 -- '\', '^', '_' or '~', when found is a Special token.
86 procedure Reset_Special_Characters;
87 -- Indicate that there is no characters that are Special tokens., which
90 procedure Set_End_Of_Line_As_Token (Value : Boolean);
91 -- Indicate if End_Of_Line is a token or not.
92 -- By default, End_Of_Line is not a token.
94 procedure Set_Comment_As_Token (Value : Boolean);
95 -- Indicate if a comment is a token or not.
96 -- By default, a comment is not a token.
98 function Set_Start_Column return Column_Number;
99 -- This routine is called with Scan_Ptr pointing to the first character
100 -- of a line. On exit, Scan_Ptr is advanced to the first non-blank
101 -- character of this line (or to the terminating format effector if the
102 -- line contains no non-blank characters), and the returned result is the
103 -- column number of this non-blank character (zero origin), which is the
104 -- value to be stored in the Start_Column scan variable.