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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- S C N G --
-- --
-- S p e c --
-- --
-- Copyright (C) 1992-2010, 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 3, 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 COPYING3. If not, go to --
-- http://www.gnu.org/licenses for a complete copy of the license. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
-- This package contains a generic lexical analyzer. This is used for scanning
-- Ada source files or text files with an Ada-like syntax, such as project
-- files. It is instantiated in Scn and Prj.Err.
with Casing; use Casing;
with Styleg;
with Types; use Types;
generic
with procedure Post_Scan;
-- Procedure called by Scan for the following tokens: Tok_Char_Literal,
-- Tok_Identifier, Tok_Real_Literal, Tok_Real_Literal, Tok_Integer_Literal,
-- Tok_String_Literal, Tok_Operator_Symbol, and Tok_Vertical_Bar. Used to
-- build Token_Node and also check for obsolescent features.
with procedure Error_Msg (Msg : String; Flag_Location : Source_Ptr);
-- Output a message at specified location
with procedure Error_Msg_S (Msg : String);
-- Output a message at current scan pointer location
with procedure Error_Msg_SC (Msg : String);
-- Output a message at the start of the current token
with procedure Error_Msg_SP (Msg : String);
-- Output a message at the start of the previous token
with package Style is new Styleg
(Error_Msg, Error_Msg_S, Error_Msg_SC, Error_Msg_SP);
-- Instantiation of Styleg with the same error reporting routines
package Scng is
procedure Initialize_Scanner (Index : Source_File_Index);
-- Initialize lexical scanner for scanning a new file referenced by Index.
-- Initialize_Scanner does not call Scan.
procedure Scan;
-- Scan scans out the next token, and advances the scan state accordingly
-- (see package Scan_State 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.
-- For tokens Char_Literal, Identifier, Real_Literal, Integer_Literal,
-- String_Literal and Operator_Symbol, Post_Scan is called after scanning.
function Determine_Token_Casing return Casing_Type;
pragma Inline (Determine_Token_Casing);
-- Determines the casing style of the current token, which is
-- either a keyword or an identifier. See also package Casing.
procedure Set_Special_Character (C : Character);
-- Indicate that one of the following character '#', '$', '?', '@', '`',
-- '\', '^', '_' or '~', when found is a Special token.
procedure Reset_Special_Characters;
-- Indicate that there is no characters that are Special tokens., which
-- is the default.
procedure Set_End_Of_Line_As_Token (Value : Boolean);
-- Indicate if End_Of_Line is a token or not.
-- By default, End_Of_Line is not a token.
procedure Set_Comment_As_Token (Value : Boolean);
-- Indicate if a comment is a token or not.
-- By default, a comment is not a token.
function Set_Start_Column return Column_Number;
-- This routine is called with Scan_Ptr pointing to the first character
-- of a line. On exit, Scan_Ptr is advanced to the first non-blank
-- character of this line (or to the terminating format effector if the
-- line contains no non-blank characters), and the returned result is the
-- column number of this non-blank character (zero origin), which is the
-- value to be stored in the Start_Column scan variable.
end Scng;
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