token.h

This software aims to create an applet and panel tools to manage a wireless interface card, such as

//
// Token.h
//
// $Id: //poco/Main/Foundation/include/Foundation/Token.h#5 $
//
// Definition of the Token class.
//
// Copyright (c) 2004, Guenter Obiltschnig/Applied Informatics.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
//
// 1. Redistributions of source code must retain the above copyright
//    notice, this list of conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright
//    notice, this list of conditions and the following disclaimer in the
//    documentation and/or other materials provided with the distribution.
//
// 3. Redistributions in any form must be accompanied by information on
//    how to obtain complete source code for this software and any
//    accompanying software that uses this software.  The source code
//    must either be included in the distribution or be available for no
//    more than the cost of distribution plus a nominal fee, and must be
//    freely redistributable under reasonable conditions.  For an
//    executable file, complete source code means the source code for all
//    modules it contains.  It does not include source code for modules or
//    files that typically accompany the major components of the operating
//    system on which the executable file runs.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
// FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
// COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
// BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
// ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//


#ifndef Foundation_Token_INCLUDED
#define Foundation_Token_INCLUDED


#ifndef Foundation_Foundation_INCLUDED
#include "Foundation/Foundation.h"
#endif
#ifndef STD_ISTREAM_INCLUDED
#include <istream>
#define STD_ISTREAM_INCLUDED
#endif


Foundation_BEGIN


class Foundation_API Token
	/// The base class for all token classes that can be
	/// registered with the StreamTokenizer.
{
public:
	enum Class
	{
		IDENTIFIER_TOKEN,
		KEYWORD_TOKEN,
		SEPARATOR_TOKEN,
		OPERATOR_TOKEN,
		STRING_LITERAL_TOKEN,
		CHAR_LITERAL_TOKEN,
		INTEGER_LITERAL_TOKEN,
		LONG_INTEGER_LITERAL_TOKEN,
		FLOAT_LITERAL_TOKEN,
		DOUBLE_LITERAL_TOKEN,
		CUSTOM0_TOKEN,
		CUSTOM1_TOKEN,
		CUSTOM2_TOKEN,
		CUSTOM3_TOKEN,
		CUSTOM4_TOKEN,
		CUSTOM5_TOKEN,
		CUSTOM6_TOKEN,
		CUSTOM7_TOKEN,
		CUSTOM8_TOKEN,
		CUSTOM9_TOKEN,
		COMMENT_TOKEN,
		WHITESPACE_TOKEN,
		EOF_TOKEN,
		INVALID_TOKEN
	};
	
	Token();
		/// Creates the Token.

	virtual ~Token();
		/// Destroys the Token.
		
	virtual bool start(char c, std::istream& istr);
		/// Checks if the given character (and, optionally,
		/// the next character in the input stream) start
		/// a valid token. Returns true if so, false
		/// otherwise.
		/// The current read position in istr must not be
		/// changed. In other words, only the peek() method
		/// of istream may be used.

	virtual void finish(std::istream& istr);
		/// Builds the token by taking c as the first
		/// character and reading the remaining characters
		/// from istr.
		
	virtual Class tokenClass() const;
		/// Returns the kind of the token.
	
	virtual const std::string& tokenString() const;
		/// Returns the token's string representation.
	
	virtual int asInteger() const;
		/// Returns an integer representation of the token.
	
	virtual double asFloat() const;
		/// Returns a floating-point representation of the token.

	virtual char asChar() const;
		/// Returns a char representation of the token.

protected:
	std::string _value;
	
private:
	Token(const Token&);
	Token& operator = (const Token&);
};


class Foundation_API InvalidToken: public Token
	/// This token class is used for signalling that
	/// an invalid character sequence has been encountered
	/// in the input stream.
{
public:
	InvalidToken();
	~InvalidToken();
	Class tokenClass() const;
};


class Foundation_API EOFToken: public Token
	/// This token class is used to signal the
	/// end of the input stream.
{
public:
	EOFToken();
	~EOFToken();
	Class tokenClass() const;
};


class Foundation_API WhitespaceToken: public Token
	/// This pseudo token class is used to eat
	/// up whitespace in between real tokens.
{
public:
	WhitespaceToken();
	~WhitespaceToken();
	Class tokenClass() const;
	bool start(char c, std::istream& istr);
	void finish(std::istream& istr);
};


Foundation_END


#endif // Foundation_Token_INCLUDED