scanner.h

C-MINUS编译器

#ifndef MY_SCANNER_H_
#define MY_SCANNER_H_
#include "Tokenizer.h"

/**:	scanner.h	header file
&
*	继承自 class Tokenizer, 从源文件中提取出单个的 token;
*	author:	lonelyforest;
*	data:	2006.03.16
*/



enum tokenType {
	// reserved Keyword
	k_INT = 0/* int */, k_ELSE/* else */,  k_RETURN/* return */,
	k_VOID/* void */, k_IF/* if */,k_WHILE/* while */,
	k_READ/* read */, k_WRITE/* write */,

	// operations
	ASSIGN/* = */, PLUS/* + */, MINUS/* - */, TIMES/* * */, DIV/* / */,
	MOD/* % */, LT/* < */, GT/* > */,

	// interpunctions
	LPARAN, RPARAN/* ( ) */, LBRACE, RBRACE/* { } */, LSQUARE, RSQUARE/* [ ] */,
	COMMA/* , */, SEMI/* ; */,

	// complex operations
	EQ/* == */, NEQ/* != */,NGT/* <= */, NLT/* >= */,

	// others
	k_EOF, k_ID, k_NUM, k_ERROR, k_NONE
};

class	Token{
public:
	Token &operator=(const Token& rh);
	tokenType	type;
	string		str;
};


/**:	class Scanner
※
*	继承Tokenizer， 从源文件提取出单个的 Token
*    忽略空白，识别关键字， 数字等等， 并且生成list文件。
*
*  重要接口 Token& nextToken() ＆ void push()
*  分别从源文件中提取一个 Token 标识符， 退回一个标识符
*
*	author:	lonelyforest;
*	data:	2006.03.16
*/
//-----------------------------------------------------------------------------
class Scanner: public Tokenizer {
public:
	Scanner(const string& filename);
	virtual ~Scanner();
	//-------------------------------------------------------------------------
	void build_key_map();	// build the keyword map;
	Token& nextToken();		// return next token !! primary interface
	void push();		// push back current token, next return it
	//-------------------------------------------------------------------------
	int	errCount() const	{ return err_count; }
	int warnCount()const	{ return warn_count; }
	void	add_warn()	{ ++warn_count; }
	void	add_err() {	++err_count;}
    //-------------------------------------------------------------------------
	void	noListFile()	{	TraceSource =false;	}
	bool	getListFile();	// create log file sourcename.log
	bool	is_good()	{ return (err_count <=0 && warn_count <=0) && Tokenizer::is_good(); }
	//-------------------------------------------------------------------------
	// if in key_word, return tokenType value else	return k_NONE;
	tokenType	reservedLookup(const string& word);
	std::vector<Token>	key_word;
protected:
    //-------------------------------------------------------------------------
	Token	m_token;	// store current token
	bool	m_pushed;	// push back curren token flag;
};

#endif