New version with STL list & stack

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Valk Richard Li 2019-08-23 17:58:51 +08:00 committed by GitHub
parent 65297d4a97
commit 0e7aceaf84
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4 changed files with 459 additions and 0 deletions

66
version0.6/main.cpp Normal file
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#include "nasal.h"
#include <cstring>
int main()
{
resource_programme_process prog;
nasal_lexer lex;
nasal_parser par;
std::string command;
std::cout<<">> nasal-- script by ValKmjolnir"<<std::endl;
std::cout<<">> input \"help\" to find help."<<std::endl;
while(1)
{
std::cout<<">> ";
std::getline(std::cin,command);
if(command=="help")
{
std::cout<<">> nasal script interpreter by ValKmjolnir"<<std::endl;
std::cout<<">> 1. |input file name to run the lexer. (-lexer)"<<std::endl;
std::cout<<">> 2. \"cls\" |clear the screen."<<std::endl;
std::cout<<">> 3. \"exit\" |shut down the program."<<std::endl;
std::cout<<">> 4. \"lexer\" |see tokens in stack."<<std::endl;
std::cout<<">> 5. \"parser\"|run parser. (-parser)"<<std::endl;
std::cout<<">> 6. \"del\" |delete all elements in stack."<<std::endl;
std::cout<<">> 7. \"run\" |run the programme in stack. (-lexer -parser)"<<std::endl;
std::cout<<">> 8. \"rs\" |check the source program."<<std::endl;
}
else if(command=="cls")
{
system("cls");
//windows system("cls);
//linux system("clear");
//macOS system("clear");
}
else if(command=="rs")
prog.print_file();
else if(command=="exit")
{
break;
}
else if(command=="lexer")
{
lex.lexer_process(prog.use_file());
lex.print_lexer();
}
else if(command=="del")
{
prog.del_file();
std::cout<<">>[Delete] Complete."<<std::endl;
}
else if(command=="parser")
{
par.parse_process(lex.return_list());//nasal::nasal_parse.print_parser(nasal::nasal_lexer);
par.print_parser();//nasal::nasal_parse.print_error();
}
else if(command=="run")
{
lex.lexer_process(prog.use_file());
par.parse_process(lex.return_list());
;//nasal::nasal_parse.print_error();
}
else
prog.input_file(command);
}
return 0;
}

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version0.6/nasal.h Normal file
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#ifndef __NASAL_H__
#define __NASAL_H__
#include "nasal_lexer.h"
#include "nasal_parser.h"
#endif

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version0.6/nasal_lexer.h Normal file
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#ifndef __NASAL_LEXER_H__
#define __NASAL_LEXER_H__
#include <iostream>
#include <fstream>
#include <list>
#include <cstring>
#define OPERATOR 1 //界符 or 运算符
#define IDENTIFIER 2 //自定义标识符
#define NUMBER 3 //数字
#define RESERVEWORD 4 //关键字
#define STRING 5 //字符串类型
#define FAIL -1 //失败
#define SCANEND -2 //扫描完成
#define ERRORFOUND -3 //异常错误
std::string reserve_word[15]=
{
"for","foreach","forindex","while",
"var","func","break","continue","return",
"if","else","elsif","nil","and","or"
};
int isReserveWord(std::string &p)
{
for(int i=0;i<15;++i)
if(reserve_word[i]==p)
return i+1;
return FAIL;
}
bool isLetter(char t)
{
return (('a'<=t) && (t<='z') || ('A'<=t) && (t<='Z'));
}
bool isNumber(char t)
{
return (('0'<=t) && (t<='9'));
}
class resource_programme_process
{
private:
char *resource;
public:
resource_programme_process()
{
resource=NULL;
resource=new char[16777216];
}
~resource_programme_process()
{
if(resource)
delete []resource;
}
char* use_file()
{
return resource;
}
void input_file(std::string& filename)
{
std::ifstream fin(filename);
if(fin.fail())
{
std::cout<<">> [Error] Cannot load file: "<<filename<<" ."<<std::endl;
fin.close();
return;
}
memset(resource,0,sizeof(char));
int i=0;
bool findnote=false;// to find the note with # at the head of line.
while(!fin.eof())
{
resource[i]=fin.get();
if(resource[i]=='\n')
findnote=false;
//when meeting '\n' the findnote is set to false then the next statement can be executed.
if(resource[i]!='#' && !findnote)
++i;
else if(resource[i]=='#')
findnote=true;
if(fin.eof())
break;
}
resource[i]='\0';
fin.close();
return;
}
void print_file()
{
if(!resource[0])
{
std::cout<<"0 null"<<std::endl;
return;
}
int line=1;
std::cout<<line<<" ";
for(int i=0;i<16777216;++i)
{
if(!resource[i])
break;
std::cout<<resource[i];
if(resource[i]=='\n')
{
++line;
std::cout<<line<<" ";
}
}
std::cout<<std::endl;
return;
}
void del_file()
{
memset(resource,0,sizeof(char));
return;
}
};
struct token
{
int line;
int type;
std::string content;
};
class nasal_lexer
{
private:
std::list<token> lexer;
public:
void scanner(int &syn,const char* source,std::string &__token,int &ptr,int &line)
{
char temp;
temp=source[ptr];
while(temp==' ' || temp=='\n' || temp=='\t' || temp=='\r' || temp<0 || temp>127)
{
++ptr;
if(temp=='\n')
++line;
temp=source[ptr];
}
__token="";
if(isLetter(temp) || temp=='_')
{
__token+=temp;
++ptr;
temp=source[ptr];
while(isLetter(temp) || isNumber(temp) || temp=='_')
{
__token+=temp;
++ptr;
temp=source[ptr];
}
syn=isReserveWord(__token);
if(syn==FAIL)
syn=IDENTIFIER;
else
syn=RESERVEWORD;
}
else if(isNumber(temp))
{
int PointCnt=0;
while(isNumber(temp))
{
__token+=temp;
++ptr;
temp=source[ptr];
if(temp=='.' && !PointCnt)
{
++PointCnt;
__token+=temp;
++ptr;
temp=source[ptr];
}
}
syn=NUMBER;
}
else if(temp=='(' || temp==')' || temp=='[' || temp==']' || temp=='{' ||
temp=='}' || temp==',' || temp==';' || temp=='|' || temp==':' ||
temp=='?' || temp=='.' || temp=='`' || temp=='\'' || temp=='&'||
temp=='%' || temp=='$' || temp=='^')
{
__token+=temp;
++ptr;
syn=OPERATOR;
}
else if(temp=='=' || temp=='+' || temp=='-' || temp=='*' || temp=='!' || temp=='/' || temp=='<' || temp=='>' || temp=='~')
{
syn=OPERATOR;
__token+=temp;
++ptr;
temp=source[ptr];
if(temp=='=')
{
__token+=temp;
++ptr;
}
}
else if(temp=='\\')
{
syn=OPERATOR;
__token+=temp;
++ptr;
temp=source[ptr];
if(temp=='=' || temp=='n' || temp=='t' || temp=='r' || temp=='\\' || temp=='\'' || temp=='\"')
{
__token+=temp;
++ptr;
}
}
else if(temp=='\"')
{
syn=STRING;
__token+=temp;
++ptr;
temp=source[ptr];
while(temp!='\"')
{
if(temp=='\\')
{
__token+=temp;
++ptr;
temp=source[ptr];
__token+=temp;
++ptr;
temp=source[ptr];
}
else
{
__token+=temp;
++ptr;
temp=source[ptr];
}
if(temp==0 || temp=='\n')
break;
}
//add the last char \"
if(temp=='\"')
{
__token+=temp;
++ptr;
}
else
__token+=" __missing_end_of_string";
}
else if(temp==0)
{
syn=SCANEND;
return;
}
else
{
syn=FAIL;
std::cout<<">>[Error] Unexpected error occurred: "<<temp<<std::endl;
system("pause");
++ptr;
return;
}
if(__token=="")
{
syn=ERRORFOUND;
std::cout<<">>[Error] Cannot identify "<<std::endl;
}
return;
}
void lexer_process(const char *source)
{
std::cout<<">>[Lexer] max size: "<<lexer.max_size()<<" ."<<std::endl;
lexer.clear();
int syn=0;//token type
int ptr=0;//pointer to one char in ResourcePrograme
int line=1;
std::string __token;
token temp;
while(syn!=SCANEND && syn!=ERRORFOUND)
{
scanner(syn,source,__token,ptr,line);
if(syn>0)//all Syn type is larger than zero
{
temp.line=line;
temp.type=syn;
temp.content=__token;
lexer.push_back(temp);
}
}
std::cout<<">>[Lexer] Complete scanning."<<std::endl;
return;
}
void print_lexer()
{
token temp;
for(std::list<token>::iterator i=lexer.begin();i!=lexer.end();++i)
{
temp=*i;
std::cout<<"line "<<temp.line<<": ";
if(temp.type==OPERATOR)
std::cout<<"( Operator | ";
else if(temp.type==IDENTIFIER)
std::cout<<"( Identifier | ";
else if(temp.type==NUMBER)
std::cout<<"( Number | ";
else if(temp.type==RESERVEWORD)
std::cout<<"( ReserveWord | ";
else if(temp.type==STRING)
std::cout<<"( String | ";
std::cout<<temp.content<<" )"<<std::endl;
}
return;
}
std::list<token>& return_list()
{
return lexer;
}
};
#endif

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version0.6/nasal_parser.h Normal file
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#ifndef __NASAL_PARSER_H__
#define __NASAL_PARSER_H__
#include <cstring>
#include <stack>
#include <list>
#include <queue>
struct parse_unit
{
int line;
std::string content;
};
class nasal_parser
{
private:
std::stack<parse_unit> parser;
public:
void parse_process(std::list<token>& lexer)
{
for(std::list<token>::iterator i=lexer.begin();i!=lexer.end();++i)
{
parse_unit temp;
temp.line=(*i).line;
temp.content=(*i).content;
parser.push(temp);
}
std::cout<<">>[Parser] Complete scanning."<<std::endl;
return;
}
void print_parser()
{
std::stack<parse_unit> temp;
while(!parser.empty())
{
temp.push(parser.top());
parser.pop();
}
int nowline=0;
if(temp.empty())
{
std::cout<<">>[Parser] Empty stack."<<std::endl;
return;
}
while(!temp.empty())
{
if(temp.top().line==nowline)
std::cout<<temp.top().content<<" ";
else
{
nowline=temp.top().line;
std::cout<<std::endl<<"line "<<nowline<<": "<<temp.top().content<<" ";
}
temp.pop();
}
std::cout<<std::endl;
return;
}
};
#endif