#include?“l(fā)ex.h“
#include?
#include?
#include?
using?namespace?std;
#include



Lex::Lex（）
{
	inFile.open（“LexInput.txt“ios::in）;
	if（!inFile）
	{
		cerr<<“LexInput.txt?doesn‘t?exist“;
		exit（1）;
	}
	
}

Lex::~Lex（）
{
	
}

string?Lex::nextToken（）
{
	int?state?=?0;
	char?ch;
	string?str?=?““;
????while（1）
	{
		switch（state）
		{
			case?0:
				ch?=?inFile.get（）;
				if（isBlank（ch））
					state?=?0;
				else?if（ch==EOF）
				{
					state?=?1;
				}
				else?if（isLetter（ch））
				{
					state?=?2;
					str?+=?ch;
				}
				else?if（isDigit（ch））
				{
					state?=?4;
					str?+=?ch;
				}
				else?if（isDoubleOperator（ch））

				{
					if?（ch==‘!‘）
					{
						str?+=ch;
						ch=inFile.get（）;
						if?（ch!=‘=‘）
						{
						cerr?<						state=8;
						}
						else
						{
							str?+=ch;
							state=6;
						}
					}
					else
					{
						str?+=ch;
						ch=inFile.get（）;
						if?（ch!=‘=‘）
						{
?????????????????????????????spBack（）;
						?????state=6;
							
						}
						?else
						{
							str?+=ch;
							state=6;
						}
					}
					
				}
				else?if（isOperator（ch））
				{
					state?=?6;
					str?+=?ch;
				}
				else?if（isSeparator（ch））
				{
					state?=?7;
					str?+=?ch;
				}
				else
				{
					state=8;
					str+=ch;
					cerr?<				
				}
				break;

			case?1:
				return?“#“;
				break;
			case?2:
				ch?=?inFile.get（）;
				if（?isLetter（ch）?||?isDigit（ch）?）
				{
					state?=?2;
					str?+=?ch;
				}
				else
				{
					spBack（）;
					state?=?3;
				}
				break;
			case?3:
				if（!isKeyword（str））
				{
					str?=?“Identifier:????????“+str;
					state?=?0;
					return?str;
				}
				else
				{
					str?=?“Keyword:???????????“+str;
					state?=?0;
					return?str;
				}
				break;
			case?4:
				ch?=?inFile.get（）;
				if（isDigit（ch））
				{
					str?+=?ch;
					state?=?4;
				}
				else
				{
					spBack（）;
					state?=?5;
				}
				break;
			case?5:
				str?=?“Number:????????????“+str;
				state?=?0;
				return?str;
				break;
			case?6:
				str?=?“Operator:??????????“+str;
				state?=?0;
				return?str;?
				break;
			case?7:
				str?=?“Separator:?????????“+str;
				
				state?=?0;
				return?str;
				break;
			case?8:
					ch?=?inFile.get（）;
				if（?（!isLetter（ch）?）&&（!isDigit（ch））&&（!isBlank（ch））&&（!isOperator（ch））&&（!isDoubleOperator（ch））&&（!isSeparator（ch））?）
				{
					state?=?8;
					str?+=?ch;
				}
				else
				{
					spBack（）;
					state?=?0;
				}
			
????????????????????cerr<					str?=“Error:?????????????“+str;
					return?str;
					break;
			default:
				cerr?<				exit（0）;
				break;
		}
	}
}

void?Lex::spBack（）
{
	inFile.seekg（-1ios::cur）;???//讓文件指針從當(dāng)前位置向文件開始方向移動1個字節(jié)
}

bool?Lex::isBlank（char?ch）
{
	ch

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件???????4601??2010-12-14?19:38??09008304_yacc\09008304_yacc.dsp

?????文件????????549??2010-12-14?19:38??09008304_yacc\09008304_yacc.dsw

?????文件??????58368??2010-12-29?00:31??09008304_yacc\09008304_yacc.ncb

?????文件??????54784??2010-12-29?00:31??09008304_yacc\09008304_yacc.opt

?????文件????????904??2010-12-29?00:22??09008304_yacc\09008304_yacc.plg

?????文件?????630866??2010-12-29?00:22??09008304_yacc\Debug\09008304_yacc.exe

?????文件?????915232??2010-12-29?00:22??09008304_yacc\Debug\09008304_yacc.ilk

?????文件????2195400??2010-12-29?00:16??09008304_yacc\Debug\09008304_yacc.pch

?????文件????1188864??2010-12-29?00:16??09008304_yacc\Debug\09008304_yacc.pdb

?????文件?????258156??2010-12-29?00:22??09008304_yacc\Debug\lex.obj

?????文件?????204491??2010-12-14?19:49??09008304_yacc\Debug\main.obj

?????文件?????292442??2010-12-14?19:49??09008304_yacc\Debug\syntax.obj

?????文件??????99328??2010-12-29?00:22??09008304_yacc\Debug\vc60.idb

?????文件?????126976??2010-12-29?00:16??09008304_yacc\Debug\vc60.pdb

?????文件???????4907??2010-12-14?19:50??09008304_yacc\lex.cpp

?????文件????????400??2010-12-14?19:49??09008304_yacc\lex.h

?????文件?????????25??2010-12-29?00:22??09008304_yacc\LexInput.txt

?????文件????????550??2010-12-14?19:31??09008304_yacc\main.cpp

?????文件?????????24??2010-12-29?00:22??09008304_yacc\outputLex.txt

?????文件????????612??2010-12-29?00:22??09008304_yacc\outputSyntax.txt

?????文件???????9424??2010-12-14?19:30??09008304_yacc\syntax.cpp

?????文件????????407??2010-12-14?19:33??09008304_yacc\syntax.h

?????文件?????374784??2010-12-29?00:31??編譯實驗報告?09008304.doc

?????文件???????4466??2010-12-02?22:10??09008304_lex\09008304_lex.dsp

?????文件????????547??2010-12-02?20:12??09008304_lex\09008304_lex.dsw

?????文件??????50176??2010-12-29?00:16??09008304_lex\09008304_lex.ncb

?????文件??????53760??2010-12-29?00:16??09008304_lex\09008304_lex.opt

?????文件????????878??2010-12-29?00:10??09008304_lex\09008304_lex.plg

?????文件?????585808??2010-12-29?00:10??09008304_lex\Debug\09008304_lex.exe

?????文件?????847900??2010-12-29?00:10??09008304_lex\Debug\09008304_lex.ilk

............此處省略18個文件信息