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------------------------------------------------------------------------------
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-- --
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-- GNAT COMPILER COMPONENTS --
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-- --
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-- S C N --
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-- --
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-- S p e c --
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-- --
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-- Copyright (C) 1992-2004 Free Software Foundation, Inc. --
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-- --
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-- GNAT is free software; you can redistribute it and/or modify it under --
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-- terms of the GNU General Public License as published by the Free Soft- --
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-- ware Foundation; either version 2, or (at your option) any later ver- --
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-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
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-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
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-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
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-- for more details. You should have received a copy of the GNU General --
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-- Public License distributed with GNAT; see file COPYING. If not, write --
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-- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
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-- Boston, MA 02110-1301, USA. --
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-- --
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-- GNAT was originally developed by the GNAT team at New York University. --
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-- Extensive contributions were provided by Ada Core Technologies Inc. --
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-- --
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------------------------------------------------------------------------------
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-- This package contains the lexical analyzer routines. This is used by the
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-- compiler for scanning Ada source files.
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with Casing; use Casing;
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with Errout; use Errout;
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with Scng;
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with Style; use Style;
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with Types; use Types;
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package Scn is
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procedure Initialize_Scanner
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(Unit : Unit_Number_Type;
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Index : Source_File_Index);
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-- Initialize lexical scanner for scanning a new file. The caller has
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-- completed the construction of the Units.Table entry for the specified
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-- Unit and Index references the corresponding source file. A special
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-- case is when Unit = No_Unit_Number, and Index corresponds to the
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-- source index for reading the configuration pragma file.
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function Determine_Token_Casing return Casing_Type;
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-- Determines the casing style of the current token, which is
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-- either a keyword or an identifier. See also package Casing.
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procedure Obsolescent_Check (S : Source_Ptr);
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-- Called to handle pragma restrictions check for usage of obsolescent
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-- character replacements during the scan.
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procedure Post_Scan;
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pragma Inline (Post_Scan);
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-- Create nodes for tokens: Char_Literal, Identifier, Real_Literal,
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-- Integer_Literal, String_Literal and Operator_Symbol.
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procedure Scan_Reserved_Identifier (Force_Msg : Boolean);
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-- This procedure is called to convert the current token, which the caller
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-- has checked is for a reserved word, to an equivalent identifier. This is
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-- of course only used in error situations where the parser can detect that
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-- a reserved word is being used as an identifier. An appropriate error
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-- message, pointing to the token, is also issued if either this is the
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-- first occurrence of misuse of this identifier, or if Force_Msg is True.
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-------------
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-- Scanner --
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-------------
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-- The scanner used by the compiler is an instantiation of the
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-- generic package Scng with routines appropriate to the compiler
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package Scanner is new Scng
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(Post_Scan => Post_Scan,
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Error_Msg => Error_Msg,
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Error_Msg_S => Error_Msg_S,
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Error_Msg_SC => Error_Msg_SC,
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Error_Msg_SP => Error_Msg_SP,
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Obsolescent_Check => Obsolescent_Check,
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Style => Style.Style_Inst);
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procedure Scan renames Scanner.Scan;
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-- Scan scans out the next token, and advances the scan state accordingly
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-- (see package Scans for details). If the scan encounters an illegal
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-- token, then an error message is issued pointing to the bad character,
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-- and Scan returns a reasonable substitute token of some kind.
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end Scn;
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