1------------------------------------------------------------------------------ 2-- -- 3-- GNAT COMPILER COMPONENTS -- 4-- -- 5-- S C N -- 6-- -- 7-- S p e c -- 8-- -- 9-- Copyright (C) 1992-2002 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 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. -- 21-- -- 22-- GNAT was originally developed by the GNAT team at New York University. -- 23-- Extensive contributions were provided by Ada Core Technologies Inc. -- 24-- -- 25------------------------------------------------------------------------------ 26 27-- This package contains the lexical analyzer routines. This is used by the 28-- compiler for scanning Ada source files. 29 30with Casing; use Casing; 31with Errout; use Errout; 32with Scng; 33with Style; use Style; 34with Types; use Types; 35 36package Scn is 37 38 procedure Initialize_Scanner 39 (Unit : Unit_Number_Type; 40 Index : Source_File_Index); 41 -- Initialize lexical scanner for scanning a new file. The caller has 42 -- completed the construction of the Units.Table entry for the specified 43 -- Unit and Index references the corresponding source file. A special 44 -- case is when Unit = No_Unit_Number, and Index corresponds to the 45 -- source index for reading the configuration pragma file. 46 47 function Determine_Token_Casing return Casing_Type; 48 -- Determines the casing style of the current token, which is 49 -- either a keyword or an identifier. See also package Casing. 50 51 procedure Post_Scan; 52 pragma Inline (Post_Scan); 53 -- Create nodes for tokens: Char_Literal, Identifier, Real_Literal, 54 -- Integer_Literal, String_Literal and Operator_Symbol. 55 56 procedure Scan_Reserved_Identifier (Force_Msg : Boolean); 57 -- This procedure is called to convert the current token, which the caller 58 -- has checked is for a reserved word, to an equivalent identifier. This is 59 -- of course only used in error situations where the parser can detect that 60 -- a reserved word is being used as an identifier. An appropriate error 61 -- message, pointing to the token, is also issued if either this is the 62 -- first occurrence of misuse of this identifier, or if Force_Msg is True. 63 64 ------------- 65 -- Scanner -- 66 ------------- 67 68 -- The scanner used by the compiler is an instantiation of the 69 -- generic package Scng with routines appropriate to the compiler 70 71 package Scanner is new Scng 72 (Post_Scan => Post_Scan, 73 Error_Msg => Error_Msg, 74 Error_Msg_S => Error_Msg_S, 75 Error_Msg_SC => Error_Msg_SC, 76 Error_Msg_SP => Error_Msg_SP, 77 Style => Style.Style_Inst); 78 79 procedure Scan renames Scanner.Scan; 80 -- Scan scans out the next token, and advances the scan state accordingly 81 -- (see package Scans for details). If the scan encounters an illegal 82 -- token, then an error message is issued pointing to the bad character, 83 -- and Scan returns a reasonable substitute token of some kind. 84 85end Scn; 86