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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- S C N --
-- --
-- S p e c --
-- --
-- Copyright (C) 1992-2004 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 2, 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. See the GNU General Public License --
-- for more details. You should have received a copy of the GNU General --
-- Public License distributed with GNAT; see file COPYING. If not, write --
-- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
-- Boston, MA 02110-1301, USA. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
-- This package contains the lexical analyzer routines. This is used by the
-- compiler for scanning Ada source files.
with Casing; use Casing;
with Errout; use Errout;
with Scng;
with Style; use Style;
with Types; use Types;
package Scn is
procedure Initialize_Scanner
(Unit : Unit_Number_Type;
Index : Source_File_Index);
-- Initialize lexical scanner for scanning a new file. The caller has
-- completed the construction of the Units.Table entry for the specified
-- Unit and Index references the corresponding source file. A special
-- case is when Unit = No_Unit_Number, and Index corresponds to the
-- source index for reading the configuration pragma file.
function Determine_Token_Casing return Casing_Type;
-- Determines the casing style of the current token, which is
-- either a keyword or an identifier. See also package Casing.
procedure Obsolescent_Check (S : Source_Ptr);
-- Called to handle pragma restrictions check for usage of obsolescent
-- character replacements during the scan.
procedure Post_Scan;
pragma Inline (Post_Scan);
-- Create nodes for tokens: Char_Literal, Identifier, Real_Literal,
-- Integer_Literal, String_Literal and Operator_Symbol.
procedure Scan_Reserved_Identifier (Force_Msg : Boolean);
-- This procedure is called to convert the current token, which the caller
-- has checked is for a reserved word, to an equivalent identifier. This is
-- of course only used in error situations where the parser can detect that
-- a reserved word is being used as an identifier. An appropriate error
-- message, pointing to the token, is also issued if either this is the
-- first occurrence of misuse of this identifier, or if Force_Msg is True.
-------------
-- Scanner --
-------------
-- The scanner used by the compiler is an instantiation of the
-- generic package Scng with routines appropriate to the compiler
package Scanner is new Scng
(Post_Scan => Post_Scan,
Error_Msg => Error_Msg,
Error_Msg_S => Error_Msg_S,
Error_Msg_SC => Error_Msg_SC,
Error_Msg_SP => Error_Msg_SP,
Obsolescent_Check => Obsolescent_Check,
Style => Style.Style_Inst);
procedure Scan renames Scanner.Scan;
-- Scan scans out the next token, and advances the scan state accordingly
-- (see package Scans for details). If the scan encounters an illegal
-- token, then an error message is issued pointing to the bad character,
-- and Scan returns a reasonable substitute token of some kind.
end Scn;
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