some functions of PDA in parser updated.

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Valk Richard Li 2019-08-14 02:26:42 +08:00 committed by GitHub
parent b4f86ba667
commit 62e1837704
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GPG Key ID: 4AEE18F83AFDEB23
6 changed files with 89 additions and 49 deletions

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@ -83,6 +83,8 @@
//statement
<func_return> ::= <return> <scalar>
<statement> ::= <definition>|<assignment>|<loop>|<choose>|<use_function>|<func_return> <;>
<loop_continue> ::= <continue>
<loop_break> ::= <break>
<statement> ::= <definition>|<assignment>|<loop>|<choose>|<use_function>|<func_return>|<loop_continue>|<loop_break> <;>
<statements> ::= <statement> <statement>
<statements> ::= <statements> <statement>

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@ -8,6 +8,7 @@
#include <thread>
#include <ctime>
#include <cmath>
#include <stack>
namespace nasal
{

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@ -1,11 +1,9 @@
#include <iostream>
#include <cstring>
#include <cstdlib>
#include "nasal.h"
int main()
{
std::string command;
std::cout<<">> nasal-- script by ValKmjolnir"<<std::endl;
std::cout<<">> input \"help\" to find help."<<std::endl;
while(1)
{
@ -13,13 +11,15 @@ int main()
std::getline(std::cin,command);
if(command=="help")
{
std::cout<<">> 1. input file name to run the nasal script."<<std::endl;
std::cout<<">> 2. command cls to clear the screen."<<std::endl;
std::cout<<">> 3. command exit to shut down the program."<<std::endl;
std::cout<<">> 4. command lexer to see tokens in stack."<<std::endl;
std::cout<<">> 5. command del to delete all elements in stack."<<std::endl;
std::cout<<">> 6. command run to run the programme in stack."<<std::endl;
std::cout<<">> 7. command rs to check the source program."<<std::endl;
std::cout<<">> nasal-- script by ValKmjolnir"<<std::endl;
std::cout<<">> 1. input file name to run the lexer."<<std::endl;
std::cout<<">> 2. command \"cls\" to clear the screen."<<std::endl;
std::cout<<">> 3. command \"exit\" to shut down the program."<<std::endl;
std::cout<<">> 4. command \"lexer\" to see tokens in stack."<<std::endl;
std::cout<<">> 5. command \"parser\" to run parser."<<std::endl;
std::cout<<">> 6. command \"del\" to delete all elements in stack."<<std::endl;
std::cout<<">> 7. command \"run\" to run the programme in stack."<<std::endl;
std::cout<<">> 8. command \"rs\" to check the source program."<<std::endl;
}
else if(command=="cls")
{
@ -41,10 +41,11 @@ int main()
nasal::nasal_var_stack.delete_all();
nasal::nasal_func_stack.delete_all();
}
else if(command=="parser")
nasal::nasal_parse.parse_work(nasal::nasal_lexer);
else if(command=="run")
{
nasal::nasal_var_stack.delete_all();
nasal::nasal_func_stack.delete_all();
;
}
else
nasal::RunProcess(command);

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@ -1,10 +1,6 @@
#ifndef __NASAL_LEXER_H__
#define __NASAL_LEXER_H__
#include <iostream>
#include <fstream>
#include <cstring>
#include "nasal_functional.h"
#define FAIL -1 //ʧ°Ü

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@ -1,55 +1,97 @@
#ifndef __NASAL_PARSE_H__
#define __NASAL_PARSE_H__
#include "nasal_lexer.h"
#include "nasal_token.h"
enum token_type
{
__stack_end,__identifier,__use_identifier,
__scalar,__function,__var,__equal,__semi,__definition
};
token_type token_type_tbl;
struct parse_unit
{
int type;
std::string content;
int line;
};
class parse
{
private:
parse_unit *content_array;
parse_unit *statement;
int len;
public:
parse();
~parse();
void content_array_set_empty();
void statement_set_empty();
std::stack<parse_unit> parser;
public:
void definition_reduction();
void parse_work(token_list&);
};
parse::parse()
void parse::definition_reduction()
{
len=0;
content_array=new parse_unit[4096];
statement=new parse_unit[1024];
}
parse::~parse()
{
if(content_array)
delete []content_array;
if(statement)
delete []statement;
}
void parse::content_array_set_empty()
{
for(int i=0;i<4096;++i)
int tbl[5];
std::stack<parse_unit> temp;
for(int i=4;i>=0;--i)
{
content_array[i].line=0;
content_array[i].type=0;
if(parser.empty())
break;
temp.push(parser.top());
tbl[i]=temp.top().type;
parser.pop();
}
if(tbl[0]==__var && tbl[1]==__identifier && tbl[2]==__equal && tbl[3]==__scalar && tbl[4]==__semi)
{
parse_unit temp_parse_unit;
temp_parse_unit.type=__definition;
temp_parse_unit.line=temp.top().line;
parser.push(temp_parse_unit);
}
else
for(int i=0;i<5;++i)
{
if(temp.empty())
break;
parser.push(temp.top());
temp.pop();
}
return;
}
void parse::statement_set_empty()
void parse::parse_work(token_list& lexer)
{
for(int i=0;i<1024;++i)
parse_unit temp_parse;
token_unit *temp=lexer.get_head();
while(temp->next)
{
statement[i].line=0;
statement[i].type=0;
temp=temp->next;
temp_parse.line=temp->line;
if(temp->content=="var")
{
token_type_tbl=__var;
temp_parse.type=token_type_tbl;
}
else if(temp->content=="=")
{
token_type_tbl=__equal;
temp_parse.type=token_type_tbl;
}
else if(temp->type==IDENTIFIER)
{
token_type_tbl=__identifier;
temp_parse.type=token_type_tbl;
}
else if(temp->content==";")
{
token_type_tbl=__semi;
temp_parse.type=token_type_tbl;
}
else if(temp->type==NUMBER || temp->type==STRING)
{
token_type_tbl=__scalar;
temp_parse.type=token_type_tbl;
}
parser.push(temp_parse);
definition_reduction();
if(parser.top().type==__definition)
std::cout<<"Definition in "<<parser.top().line<<std::endl;
}
return;
}

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@ -1,8 +1,6 @@
#ifndef __NASAL_PRINT_H__
#define __NASAL_PRINT_H__
#include<iostream>
#include<cstring>
#include "nasal_hash.cpp"
#include "nasal_list.cpp"