diff --git a/balloon/balloon_lexer.h b/balloon/balloon_lexer.h
deleted file mode 100644
index ac41b41..0000000
--- a/balloon/balloon_lexer.h
+++ /dev/null
@@ -1,593 +0,0 @@
-#ifndef __BALLOON_LEXER_H__
-#define __BALLOON_LEXER_H__
-
-/*
-	reserve words are those below
-	and they are also the reserve words of nasal
-*/
-std::string reserve_word[14]=
-{
-	"for","foreach","forindex","while",
-	"var","func","break","continue","return",
-	"if","else","elsif","and","or"
-};
-
-int is_reserve_word(std::string str)
-{
-	for(int i=0;i<14;++i)
-		if(reserve_word[i]==str)
-			return __reserve_word;
-	return __token_identifier;
-}
-
-/*
-	check if the generated string can be put to number
-*/
-bool check_number(std::string str)
-{
-	if(str.length()>1 && str[0]=='-')
-	{
-		// this statements only used in input
-		// but in lexer this statements are useless
-		std::string temp="";
-		for(int i=1;i<str.length();++i)
-			temp+=str[i];
-		str=temp;
-	}
-	if(str.length()==1)
-		return true;
-	else if(str.length()==2 && '0'<str[0] && str[0]<='9' && '0'<=str[1] && str[1]<='9')
-		return true;
-	else if(str.length()>=3 && str[0]=='0' && str[1]=='x')
-	{
-		for(int i=2;i<str.length();++i)
-		{
-			if('0'<=str[i] && str[i]<='9' || 'a'<=str[i] && str[i]<='f' || 'A'<=str[i] && str[i]<='F')
-				;
-			else
-				return false;
-		}
-		return true;
-	}
-	else if(str.length()>=3 && str[0]=='0' && str[1]=='o')
-	{
-		for(int i=2;i<str.length();++i)
-		{
-			if('0'<=str[i] && str[i]<='7')
-				;
-			else
-				return false;
-		}
-		return true;
-	}
-	else
-	{
-		int dotcnt=0;
-		for(int i=0;i<str.length();++i)
-		{
-			if(str[i]=='.')
-				++dotcnt;
-			else if(!('0'<=str[i] && str[i]<='9'))
-				return false;
-		}
-		if(dotcnt>1)
-			return false;
-		if(str[0]=='.')
-			return false;
-		if(!dotcnt && str[0]=='0')
-			return false;
-		return true;
-	}
-	return false;
-}
-
-/*
-	use std::list<char> to store resource codes
-	and if you continue adding files
-	the codes will be added behind files that have
-	been added in before
-*/
-class resource_file
-{
-	private:
-		std::list<char> libsource;   // place for lib code
-		std::list<char> resource;    // place for user code
-		std::list<char> totalsource; // link lib and user code
-	public:
-		void set_clear()
-		{
-			resource.clear();
-			libsource.clear();
-			totalsource.clear();
-			return;
-		}
-		void clear_lib_code()
-		{
-			libsource.clear();
-			return;
-		}
-		void add_lib()
-		{
-			libsource.clear();
-			std::string lib_name;
-			lib_name="lib/math.nas";
-			if(access("lib/math.nas",0))
-				std::cout<<">>[Resource] lack lib file: lib/math.nas ."<<std::endl;
-			else
-				input_lib_file(lib_name);
-			lib_name="lib/io.nas";
-			if(access("lib/io.nas",0))
-				std::cout<<">>[Resource] lack lib file: lib/io.nas ."<<std::endl;
-			else
-				input_lib_file(lib_name);
-			lib_name="lib/basics.nas";
-			if(access("lib/basics.nas",0))
-				std::cout<<">>[Resource] lack lib file: lib/basics.nas ."<<std::endl;
-			else
-				input_lib_file(lib_name);
-			return;
-		}
-		void input_lib_file(std::string filename)
-		{
-			std::ifstream fin(filename,std::ios::binary);
-			if(fin.fail())
-			{
-				std::cout<<">>[Resource] cannot find a file named \'"<<filename<<"\' ."<<std::endl;
-				return;
-			}
-			char c;
-			while(!fin.eof())
-			{
-				c=fin.get(); 
-				if(fin.eof())
-					break;
-				if(0<=c && c<128)
-					libsource.push_back(c);
-				else
-					libsource.push_back(' ');
-			}
-			libsource.push_back('\n');
-			return;
-		}
-		void input_file(std::string filename)
-		{
-			std::ifstream fin(filename,std::ios::binary);
-			if(fin.fail())
-			{
-				std::cout<<">>[Resource] cannot find a file named \'"<<filename<<"\' ."<<std::endl;
-				return;
-			}
-			char c;
-			while(!fin.eof())
-			{
-				c=fin.get(); 
-				if(fin.eof())
-					break;
-				if(0<=c && c<128)
-					resource.push_back(c);
-				else
-					resource.push_back(' ');
-			}
-			resource.push_back('\n');
-			return;
-		}
-		std::list<char>& get_resource()
-		{
-			totalsource.clear();
-			for(std::list<char>::iterator i=libsource.begin();i!=libsource.end();++i)
-				totalsource.push_back(*i);
-			for(std::list<char>::iterator i=resource.begin();i!=resource.end();++i)
-				totalsource.push_back(*i);
-			return totalsource;
-		}
-		void print_file(bool withlib)
-		{
-			int line=1;
-			std::cout<<line<<"	";
-			if(withlib)
-			{
-				for(std::list<char>::iterator i=libsource.begin();i!=libsource.end();++i)
-				{
-					if(32<=*i && *i<128 || *i=='\n')
-						std::cout<<*i;
-					else if(*i=='\t')
-						std::cout<<"    ";
-					if(*i=='\n')
-					{
-						++line;
-						std::cout<<line<<"	";
-					}
-				}
-			}
-			for(std::list<char>::iterator i=resource.begin();i!=resource.end();++i)
-			{
-				if(32<=*i && *i<128 || *i=='\n')
-					std::cout<<*i;
-				else if(*i=='\t')
-					std::cout<<"    ";
-				if(*i=='\n')
-				{
-					++line;
-					std::cout<<line<<"	";
-				}
-			}
-			std::cout<<std::endl;
-			return;
-		}
-};
-
-struct token
-{
-	int line;
-	int type;
-	std::string str;
-};
-/*
-	lexer can recognize:
-		number: 100(int) 0.001(double) 0xdeadbeef(hex) 0o1701(oct)
-		string: "str" 'str'
-		identifier
-			reserve word
-			normal identifier: ID and id is different
-		operator
-*/
-class balloon_lexer
-{
-	private:
-		int error;
-		std::list<token> token_list;
-		std::list<token> detail_token;
-	public:
-		void set_clear()
-		{
-			token_list.clear();
-			detail_token.clear();
-			return;
-		}
-		void print_token_list()
-		{
-			for(std::list<token>::iterator i=token_list.begin();i!=token_list.end();++i)
-			{
-				std::cout<<"( ";
-				print_token(i->type);
-				std::cout<<" | "<<i->str<<" )"<<std::endl;
-			}
-			return;
-		}
-		void print_detail_token_list()
-		{
-			for(std::list<token>::iterator i=detail_token.begin();i!=detail_token.end();++i)
-			{
-				std::cout<<"( ";
-				print_detail_token(i->type);
-				std::cout<<" | "<<i->str<<" )"<<std::endl;
-			}
-			return;
-		}
-		void scanner(std::list<char>& res)
-		{
-			token_list.clear();
-			error=0;
-			
-			int line=1;
-			std::string token_str;
-			std::list<char>::iterator ptr=res.begin();
-			while(ptr!=res.end())
-			{
-				while(*ptr==' ' || *ptr=='\n' || *ptr=='\t' || *ptr=='\r' || *ptr<0 || *ptr>127)
-				{
-					if(*ptr=='\n')
-						++line;
-					++ptr;
-					if(ptr==res.end())
-						break;
-				}
-				if(ptr==res.end())
-					break;
-				if(*ptr=='_' || ('a'<=*ptr && *ptr<='z') || ('A'<=*ptr && *ptr<='Z'))
-				{
-					token_str="";
-					while(*ptr=='_' || ('a'<=*ptr && *ptr<='z') || ('A'<=*ptr && *ptr<='Z') || ('0'<=*ptr && *ptr<='9'))
-					{
-						token_str+=*ptr;
-						++ptr;
-						if(ptr==res.end())
-							break;
-					}
-					if(*ptr=='.')
-					{
-						++ptr;
-						if(ptr!=res.end() && *ptr=='.')
-						{
-							++ptr;
-							if(ptr!=res.end() && *ptr=='.')
-							{
-								token_str+="...";
-								++ptr;
-							}
-							else
-							{
-								--ptr;
-								--ptr;
-							}
-						}
-						else
-							--ptr;
-					}
-					token new_token;
-					new_token.line=line;
-					new_token.type=is_reserve_word(token_str);
-					new_token.str=token_str;
-					token_list.push_back(new_token);
-					if(ptr==res.end())
-						break;
-				}
-				else if('0'<=*ptr && *ptr<='9')
-				{
-					token_str="";
-					while(('0'<=*ptr && *ptr<='9') || ('a'<=*ptr && *ptr<='f') || ('A'<=*ptr && *ptr<='F') || *ptr=='.' || *ptr=='x' || *ptr=='o')
-					{
-						token_str+=*ptr;
-						++ptr;
-						if(ptr==res.end())
-							break;
-					}
-					if(!check_number(token_str))
-					{
-						++error;
-						std::cout<<">>[Lexer-error] line "<<line<<": error number "<<token_str<<"."<<std::endl;
-						token_str="0";
-					}
-					token new_token;
-					new_token.line=line;
-					new_token.type=__token_number;
-					new_token.str=token_str;
-					token_list.push_back(new_token);
-					if(ptr==res.end())
-						break;
-				}
-				else if(*ptr=='(' || *ptr==')' || *ptr=='[' || *ptr==']' || *ptr=='{' ||
-						*ptr=='}' || *ptr==',' || *ptr==';' || *ptr=='|' || *ptr==':' ||
-						*ptr=='?' || *ptr=='.' || *ptr=='`' || *ptr=='&' || *ptr=='@' ||
-						*ptr=='%' || *ptr=='$' || *ptr=='^' || *ptr=='\\')
-				{
-					token_str="";
-					token_str+=*ptr;
-					token new_token;
-					new_token.line=line;
-					new_token.type=__token_operator;
-					new_token.str=token_str;
-					token_list.push_back(new_token);
-					++ptr;
-					if(ptr==res.end())
-						break;
-				}
-				else if(*ptr=='\'' || *ptr=='\"')
-				{
-					char str_begin=*ptr;
-					token_str="";
-					++ptr;
-					if(ptr==res.end())
-						break;
-					while(*ptr!=str_begin && *ptr!='\n')
-					{
-						token_str+=*ptr;
-						if(*ptr=='\\')
-						{
-							++ptr;
-							if(ptr!=res.end())
-							{
-								token_str+=*ptr;
-								++ptr;
-							}
-						}
-						else
-							++ptr;
-						if(ptr==res.end())
-							break;
-					}
-					if(ptr==res.end() || *ptr!=str_begin)
-					{
-						++error;
-						std::cout<<">>[Lexer-error] line "<<line<<": this string must have a \' "<<str_begin<<" \' as its end."<<std::endl;
-					}
-					else
-					{
-						token new_token;
-						new_token.line=line;
-						new_token.type=__token_string;
-						new_token.str=token_str;
-						token_list.push_back(new_token);
-					}
-					++ptr;
-					if(ptr==res.end())
-						break;
-				}
-				else if(*ptr=='=' || *ptr=='+' || *ptr=='-' || *ptr=='*' || *ptr=='!' || *ptr=='/' || *ptr=='<' || *ptr=='>' || *ptr=='~')
-				{
-					token_str="";
-					token_str+=*ptr;
-					++ptr;
-					if(ptr!=res.end() && *ptr=='=')
-					{
-						token_str+=*ptr;
-						++ptr;
-					}
-					token new_token;
-					new_token.line=line;
-					new_token.type=__token_operator;
-					new_token.str=token_str;
-					token_list.push_back(new_token);
-					if(ptr==res.end())
-						break;
-				}
-				else if(*ptr=='#')
-				{
-					while(ptr!=res.end() && *ptr!='\n')++ptr;
-					if(ptr==res.end())
-						break;
-				}
-				else
-				{
-					++error;
-					std::cout<<">>[Lexer-error] line "<<line<<": unknown char."<<std::endl;
-					++ptr;
-				}
-			}
-			std::cout<<">>[Pre-lexer] complete scanning."<<error<<" error(s)."<<std::endl;
-			return;
-		}
-		void generate_detail_token()
-		{
-			token detail;
-			detail_token.clear();
-			for(std::list<token>::iterator i=token_list.begin();i!=token_list.end();++i)
-			{
-				if(i->type==__token_number)
-				{
-					detail.line=i->line;
-					detail.str=i->str;
-					detail.type=__number;
-					detail_token.push_back(detail);
-				}
-				else if(i->type==__token_string)
-				{
-					detail.line=i->line;
-					detail.str=i->str;
-					detail.type=__string;
-					detail_token.push_back(detail);
-				}
-				else if(i->type==__reserve_word)
-				{
-					detail.line=i->line;
-					detail.str=i->str;
-					if(i->str=="for")
-						detail.type=__for;
-					else if(i->str=="foreach")
-						detail.type=__foreach;
-					else if(i->str=="forindex")
-						detail.type=__forindex;
-					else if(i->str=="while")
-						detail.type=__while;
-					else if(i->str=="var")
-						detail.type=__var;
-					else if(i->str=="func")
-						detail.type=__func;
-					else if(i->str=="break")
-						detail.type=__break;
-					else if(i->str=="continue")
-						detail.type=__continue;
-					else if(i->str=="return")
-						detail.type=__return;
-					else if(i->str=="if")
-						detail.type=__if;
-					else if(i->str=="else")
-						detail.type=__else;
-					else if(i->str=="elsif")
-						detail.type=__elsif;
-					else if(i->str=="nil")
-						detail.type=__nil;
-					else if(i->str=="and")
-						detail.type=__and_operator;
-					else if(i->str=="or")
-						detail.type=__or_operator;
-					detail_token.push_back(detail);
-				}
-				else if(i->type==__token_identifier)
-				{
-					detail.line=i->line;
-					detail.str=i->str;
-					if(i->str.length()<=3)
-						detail.type=__id;
-					else
-					{
-						std::string tempstr=i->str;
-						int strback=tempstr.length()-1;
-						if(tempstr[strback]=='.' && tempstr[strback-1]=='.' && tempstr[strback-2]=='.')
-							detail.type=__dynamic_id;
-						else
-							detail.type=__id;
-					}
-					detail_token.push_back(detail);
-				}
-				else if(i->type==__token_operator)
-				{
-					detail.line=i->line;
-					detail.str=i->str;
-					if(i->str=="+")
-						detail.type=__add_operator;
-					else if(i->str=="-")
-						detail.type=__sub_operator;
-					else if(i->str=="*")
-						detail.type=__mul_operator;
-					else if(i->str=="/")
-						detail.type=__div_operator;
-					else if(i->str=="~")
-						detail.type=__link_operator;
-					else if(i->str=="+=")
-						detail.type=__add_equal;
-					else if(i->str=="-=")
-						detail.type=__sub_equal;
-					else if(i->str=="*=")
-						detail.type=__mul_equal;
-					else if(i->str=="/=")
-						detail.type=__div_equal;
-					else if(i->str=="~=")
-						detail.type=__link_equal;
-					else if(i->str=="=")
-						detail.type=__equal;
-					else if(i->str=="==")
-						detail.type=__cmp_equal;
-					else if(i->str=="!=")
-						detail.type=__cmp_not_equal;
-					else if(i->str=="<")
-						detail.type=__cmp_less;
-					else if(i->str=="<=")
-						detail.type=__cmp_less_or_equal;
-					else if(i->str==">")
-						detail.type=__cmp_more;
-					else if(i->str==">=")
-						detail.type=__cmp_more_or_equal;
-					else if(i->str==";")
-						detail.type=__semi;
-					else if(i->str==".")
-						detail.type=__dot;
-					else if(i->str==":")
-						detail.type=__colon;
-					else if(i->str==",")
-						detail.type=__comma;
-					else if(i->str=="!")
-						detail.type=__nor_operator;
-					else if(i->str=="[")
-						detail.type=__left_bracket;
-					else if(i->str=="]")
-						detail.type=__right_bracket;
-					else if(i->str=="(")
-						detail.type=__left_curve;
-					else if(i->str==")")
-						detail.type=__right_curve;
-					else if(i->str=="{")
-						detail.type=__left_brace;
-					else if(i->str=="}")
-						detail.type=__right_brace;
-					else
-					{
-						++error;
-						std::cout<<">>[Lexer-error] line "<<detail.line<<": unknown operator."<<std::endl;
-					}
-					detail_token.push_back(detail);
-				}
-			}
-			std::cout<<">>[Lexer] complete generating."<<error<<" error(s)."<<std::endl;
-			return;
-		}
-		std::list<token>& get_detail_token()
-		{
-			return detail_token;
-		}
-		int get_error()
-		{
-			return error;
-		}
-};
-#endif