diff --git a/lab.cpp b/lab.cpp
index d4ab5d9..49ce4d6 100644
--- a/lab.cpp
+++ b/lab.cpp
@@ -72,6 +72,45 @@ int main()
 	qthash.Append("int",&a,"int");
 	qt.Append(&qthash,"hash");
 	qt.PrintList();
+	std::cout<<std::endl;
+	
+	NasalList _l;
+	_l.Append(&a,"int");
+	_l.SetSize(10);
+	_l.PrintList();
+	std::cout<<std::endl;
+	_l.SetSize(3);
+	_l.PrintList();
+	std::cout<<std::endl;
+	
+	_l.SetSize(0);
+	_l.PrintList();
+	std::cout<<std::endl;
+	_l.Append(&a,"int");
+	_l.Append(&a,"int");
+	_l.Append(&a,"int");
+	_l.Append(&a,"int");
+	_l.Append(&a,"int");
+	_l.Append(&a,"int");
+	NasalList _k;
+	_l.PrintList();
+	std::cout<<std::endl;
+	_k=_l.SubVec(9,4);
+	_k.PrintList();
+	std::cout<<std::endl;
+	_k=_l.SubVec(1,10);
+	_k.PrintList();
+	std::cout<<std::endl;
+	
+	NasalList _m;
+	var _temp=_k.Pop();
+	_m.Append(&_temp,"var");
+	_k.PrintList();
+	std::cout<<std::endl;
+	_m.PrintList();
+	std::cout<<std::endl;
+	qthash.Append("var",&_temp,"var");
+	qthash.PrintHash();
 	
 	return 0;
 }
diff --git a/nasal_hash.cpp b/nasal_hash.cpp
index 7899f97..f048ee2 100644
--- a/nasal_hash.cpp
+++ b/nasal_hash.cpp
@@ -12,6 +12,7 @@ NasalHash::NasalHash()
 	head->data=NULL;
 	head->next=NULL;
 }
+
 NasalHash::NasalHash(NasalHash &Source)
 {
 	HashUnit *temp;
@@ -34,37 +35,37 @@ NasalHash::NasalHash(NasalHash &Source)
 			temp->data=new int;
 			*((int *)temp->data)=*((int *)SourceTemp->data);
 		}
-		if(temp->Type=="float")
+		else if(temp->Type=="float")
 		{
 			temp->data=new float;
 			*((float *)temp->data)=*((float *)SourceTemp->data);
 		}
-		if(temp->Type=="double")
+		else if(temp->Type=="double")
 		{
 			temp->data=new double;
 			*((double *)temp->data)=*((double *)SourceTemp->data);
 		}
-		if(temp->Type=="char")
+		else if(temp->Type=="char")
 		{
 			temp->data=new char;
 			*((char *)temp->data)=*((char *)SourceTemp->data);
 		}
-		if(temp->Type=="long long int")
+		else if(temp->Type=="long long int")
 		{
 			temp->data=new long long int;
 			*((long long int *)temp->data)=*((long long int *)SourceTemp->data);
 		}
-		if(temp->Type=="string")
+		else if(temp->Type=="string")
 		{
 			temp->data=new std::string;
 			*((std::string *)temp->data)=*((std::string *)SourceTemp->data);
 		}
-		if(temp->Type=="array")
+		else if(temp->Type=="array")
 		{
 			temp->data=new NasalList;
 			*((NasalList *)temp->data)=*((NasalList *)SourceTemp->data);
 		}
-		if(temp->Type=="hash")
+		else if(temp->Type=="hash")
 		{
 			temp->data=new NasalHash;
 			*((NasalHash *)temp->data)=*((NasalHash *)SourceTemp->data);
@@ -72,6 +73,7 @@ NasalHash::NasalHash(NasalHash &Source)
 		temp->next=NULL;
 	}
 }
+
 NasalHash::~NasalHash()
 {
 	HashUnit *temp=head;
@@ -82,19 +84,19 @@ NasalHash::~NasalHash()
 		{
 			if(temp->Type=="int")
 				delete (int *)temp->data;
-			if(temp->Type=="float")
+			else if(temp->Type=="float")
 				delete (float *)temp->data;
-			if(temp->Type=="double")
+			else if(temp->Type=="double")
 				delete (double *)temp->data;
-			if(temp->Type=="char")
+			else if(temp->Type=="char")
 				delete (char *)temp->data;
-			if(temp->Type=="long long int")
+			else if(temp->Type=="long long int")
 				delete (long long int *)temp->data;
-			if(temp->Type=="string")
+			else if(temp->Type=="string")
 				delete (std::string *)temp->data;
-			if(temp->Type=="array")
+			else if(temp->Type=="array")
 				delete (NasalList *)temp->data;
-			if(temp->Type=="hash")
+			else if(temp->Type=="hash")
 				delete (NasalHash *)temp->data;
 		}
 		delete temp;
@@ -104,23 +106,24 @@ NasalHash::~NasalHash()
 	{
 		if(temp->Type=="int")
 			delete (int *)temp->data;
-		if(temp->Type=="float")
+		else if(temp->Type=="float")
 			delete (float *)temp->data;
-		if(temp->Type=="double")
+		else if(temp->Type=="double")
 			delete (double *)temp->data;
-		if(temp->Type=="char")
+		else if(temp->Type=="char")
 			delete (char *)temp->data;
-		if(temp->Type=="long long int")
+		else if(temp->Type=="long long int")
 			delete (long long int *)temp->data;
-		if(temp->Type=="string")
+		else if(temp->Type=="string")
 			delete (std::string *)temp->data;
-		if(temp->Type=="array")
+		else if(temp->Type=="array")
 			delete (NasalList *)temp->data;
-		if(temp->Type=="hash")
+		else if(temp->Type=="hash")
 			delete (NasalHash *)temp->data;
 	}
 	delete temp;
 }
+
 void NasalHash::PrintHash()
 {
 	HashUnit *temp=head;
@@ -133,22 +136,22 @@ void NasalHash::PrintHash()
 		{
 			if(temp->Type=="int")
 				std::cout<<*((int *)temp->data)<<", ";
-			if(temp->Type=="float")
+			else if(temp->Type=="float")
 				std::cout<<*((float *)temp->data)<<", ";
-			if(temp->Type=="double")
+			else if(temp->Type=="double")
 				std::cout<<*((double *)temp->data)<<", ";
-			if(temp->Type=="char")
+			else if(temp->Type=="char")
 				std::cout<<"\""<<*((char *)temp->data)<<"\", ";
-			if(temp->Type=="long long int")
+			else if(temp->Type=="long long int")
 				std::cout<<*((long long int *)temp->data)<<", ";
-			if(temp->Type=="string")
+			else if(temp->Type=="string")
 				std::cout<<"\""<<*((std::string *)temp->data)<<"\", ";
-			if(temp->Type=="array")
+			else if(temp->Type=="array")
 			{
 				((NasalList *)temp->data)->PrintList();
 				std::cout<<", ";
 			}
-			if(temp->Type=="hash")
+			else if(temp->Type=="hash")
 			{
 				((NasalHash *)temp->data)->PrintHash();
 				std::cout<<", ";
@@ -158,24 +161,25 @@ void NasalHash::PrintHash()
 		{
 			if(temp->Type=="int")
 				std::cout<<*((int *)temp->data);
-			if(temp->Type=="float")
+			else if(temp->Type=="float")
 				std::cout<<*((float *)temp->data);
-			if(temp->Type=="double")
+			else if(temp->Type=="double")
 				std::cout<<*((double *)temp->data);
-			if(temp->Type=="char")
+			else if(temp->Type=="char")
 				std::cout<<"\""<<*((char *)temp->data)<<"\"";
-			if(temp->Type=="long long int")
+			else if(temp->Type=="long long int")
 				std::cout<<*((long long int *)temp->data);
-			if(temp->Type=="string")
+			else if(temp->Type=="string")
 				std::cout<<"\""<<*((std::string *)temp->data)<<"\"";
-			if(temp->Type=="array")
+			else if(temp->Type=="array")
 				((NasalList *)temp->data)->PrintList();
-			if(temp->Type=="hash")
+			else if(temp->Type=="hash")
 				((NasalHash *)temp->data)->PrintHash();
 		}
 	}
 	std::cout<<"}";
 }
+
 void NasalHash::Append(const char *VariaName,void *AppendData,const char *TypeName)
 {
 	NasalHash TempHash;//sometimes user may use n.append(n)
@@ -231,6 +235,50 @@ void NasalHash::Append(const char *VariaName,void *AppendData,const char *TypeNa
 		NewHashMember->data=new NasalHash;
 		*((NasalHash *)NewHashMember->data)=TempHash;
 	}
+	else if(TypeName=="var")
+	{
+		NewHashMember->Type=(*(var *)AppendData).Type;
+		if((*(var *)AppendData).Type=="int")
+		{
+			NewHashMember->data=new int;
+			*((int *)NewHashMember->data)=*((int *)(*(var *)AppendData).data);
+		}
+		else if((*(var *)AppendData).Type=="float")
+		{
+			NewHashMember->data=new float;
+			*((float *)NewHashMember->data)=*((float *)(*(var *)AppendData).data);
+		}
+		else if((*(var *)AppendData).Type=="double")
+		{
+			NewHashMember->data=new double;
+			*((double *)NewHashMember->data)=*((double *)(*(var *)AppendData).data);
+		}
+		else if((*(var *)AppendData).Type=="char")
+		{
+			NewHashMember->data=new char;
+			*((char *)NewHashMember->data)=*((char *)(*(var *)AppendData).data);
+		}
+		else if((*(var *)AppendData).Type=="long long int")
+		{
+			NewHashMember->data=new long long int;
+			*((long long int *)NewHashMember->data)=*((long long int *)(*(var *)AppendData).data);
+		}
+		else if((*(var *)AppendData).Type=="string")
+		{
+			NewHashMember->data=new std::string;
+			*((std::string *)NewHashMember->data)=*((std::string *)(*(var *)AppendData).data);
+		}
+		else if((*(var *)AppendData).Type=="array")
+		{
+			NewHashMember->data=new NasalList;
+			*((NasalList *)NewHashMember->data)=*((NasalList *)(*(var *)AppendData).data);
+		}
+		else if((*(var *)AppendData).Type=="hash")
+		{
+			NewHashMember->data=new NasalHash;
+			*((NasalHash *)NewHashMember->data)=*((NasalHash *)(*(var *)AppendData).data);
+		}
+	}
 	NewHashMember->next=NULL;
 }
 int NasalHash::Contains(const char *VariaName)
@@ -244,6 +292,7 @@ int NasalHash::Contains(const char *VariaName)
 	}
 	return 0;
 }
+
 NasalList NasalHash::Keys()
 {
 	NasalList FeedBackList;
@@ -255,6 +304,7 @@ NasalList NasalHash::Keys()
 	}
 	return FeedBackList;
 }
+
 void NasalHash::Delete(const char *VariaName)
 {
 	HashUnit *temp=head;
@@ -268,19 +318,19 @@ void NasalHash::Delete(const char *VariaName)
 			LastNode->next=temp->next;
 			if(temp->Type=="int")
 				delete (int *)temp->data;
-			if(temp->Type=="float")
+			else if(temp->Type=="float")
 				delete (float *)temp->data;
-			if(temp->Type=="double")
+			else if(temp->Type=="double")
 				delete (double *)temp->data;
-			if(temp->Type=="char")
+			else if(temp->Type=="char")
 				delete (char *)temp->data;
-			if(temp->Type=="long long int")
+			else if(temp->Type=="long long int")
 				delete (long long int *)temp->data;
-			if(temp->Type=="string")
+			else if(temp->Type=="string")
 				delete (std::string *)temp->data;
-			if(temp->Type=="array")
+			else if(temp->Type=="array")
 				delete (NasalList *)temp->data;
-			if(temp->Type=="hash")
+			else if(temp->Type=="hash")
 				delete (NasalHash *)temp->data;
 			delete temp;
 			return;
@@ -289,6 +339,7 @@ void NasalHash::Delete(const char *VariaName)
 	std::cout<<"[Error]: Could not find this element \""<<VariaName<<"\"."<<std::endl;
 	return;
 }
+
 NasalHash& NasalHash::operator=(const NasalHash &Source)
 {
 	HashUnit *temp=head;
@@ -300,19 +351,19 @@ NasalHash& NasalHash::operator=(const NasalHash &Source)
 		{
 			if(temp->Type=="int")
 				delete (int *)temp->data;
-			if(temp->Type=="float")
+			else if(temp->Type=="float")
 				delete (float *)temp->data;
-			if(temp->Type=="double")
+			else if(temp->Type=="double")
 				delete (double *)temp->data;
-			if(temp->Type=="char")
+			else if(temp->Type=="char")
 				delete (char *)temp->data;
-			if(temp->Type=="long long int")
+			else if(temp->Type=="long long int")
 				delete (long long int *)temp->data;
-			if(temp->Type=="string")
+			else if(temp->Type=="string")
 				delete (std::string *)temp->data;
-			if(temp->Type=="array")
+			else if(temp->Type=="array")
 				delete (NasalList *)temp->data;
-			if(temp->Type=="hash")
+			else if(temp->Type=="hash")
 				delete (NasalHash *)temp->data;
 		}
 		delete temp;
@@ -322,19 +373,19 @@ NasalHash& NasalHash::operator=(const NasalHash &Source)
 	{
 		if(temp->Type=="int")
 			delete (int *)temp->data;
-		if(temp->Type=="float")
+		else if(temp->Type=="float")
 			delete (float *)temp->data;
-		if(temp->Type=="double")
+		else if(temp->Type=="double")
 			delete (double *)temp->data;
-		if(temp->Type=="char")
+		else if(temp->Type=="char")
 			delete (char *)temp->data;
-		if(temp->Type=="long long int")
+		else if(temp->Type=="long long int")
 			delete (long long int *)temp->data;
-		if(temp->Type=="string")
+		else if(temp->Type=="string")
 			delete (std::string *)temp->data;
-		if(temp->Type=="array")
+		else if(temp->Type=="array")
 			delete (NasalList *)temp->data;
-		if(temp->Type=="hash")
+		else if(temp->Type=="hash")
 			delete (NasalHash *)temp->data;
 	}
 	delete temp;
@@ -354,37 +405,37 @@ NasalHash& NasalHash::operator=(const NasalHash &Source)
 			temp->data=new int;
 			*((int *)temp->data)=*((int *)SourceTemp->data);
 		}
-		if(temp->Type=="float")
+		else if(temp->Type=="float")
 		{
 			temp->data=new float;
 			*((float *)temp->data)=*((float *)SourceTemp->data);
 		}
-		if(temp->Type=="double")
+		else if(temp->Type=="double")
 		{
 			temp->data=new double;
 			*((double *)temp->data)=*((double *)SourceTemp->data);
 		}
-		if(temp->Type=="char")
+		else if(temp->Type=="char")
 		{
 			temp->data=new char;
 			*((char *)temp->data)=*((char *)SourceTemp->data);
 		}
-		if(temp->Type=="long long int")
+		else if(temp->Type=="long long int")
 		{
 			temp->data=new long long int;
 			*((long long int *)temp->data)=*((long long int *)SourceTemp->data);
 		}
-		if(temp->Type=="string")
+		else if(temp->Type=="string")
 		{
 			temp->data=new std::string;
 			*((std::string *)temp->data)=*((std::string *)SourceTemp->data);
 		}
-		if(temp->Type=="array")
+		else if(temp->Type=="array")
 		{
 			temp->data=new NasalList;
 			*((NasalList *)temp->data)=*((NasalList *)SourceTemp->data);
 		}
-		if(temp->Type=="hash")
+		else if(temp->Type=="hash")
 		{
 			temp->data=new NasalHash;
 			*((NasalHash *)temp->data)=*((NasalHash *)SourceTemp->data);
diff --git a/nasal_hash.h b/nasal_hash.h
index 6d9acd1..e60cbba 100644
--- a/nasal_hash.h
+++ b/nasal_hash.h
@@ -7,6 +7,9 @@
 
 namespace nasal
 {
+#ifndef nil
+#define nil -1
+#endif
 
 struct HashUnit
 {
diff --git a/nasal_list.cpp b/nasal_list.cpp
index da6fef1..30e4918 100644
--- a/nasal_list.cpp
+++ b/nasal_list.cpp
@@ -12,6 +12,7 @@ NasalList::NasalList()
 	head->data=NULL;
 	head->next=NULL;
 }
+
 NasalList::NasalList(NasalList &Source)
 {
 	ListUnit *temp;
@@ -32,44 +33,49 @@ NasalList::NasalList(NasalList &Source)
 			temp->data=new int;
 			*((int *)temp->data)=*((int *)SourceTemp->data);
 		}
-		if(temp->Type=="float")
+		else if(temp->Type=="float")
 		{
 			temp->data=new float;
 			*((float *)temp->data)=*((float *)SourceTemp->data);
 		}
-		if(temp->Type=="double")
+		else if(temp->Type=="double")
 		{
 			temp->data=new double;
 			*((double *)temp->data)=*((double *)SourceTemp->data);
 		}
-		if(temp->Type=="char")
+		else if(temp->Type=="char")
 		{
 			temp->data=new char;
 			*((char *)temp->data)=*((char *)SourceTemp->data);
 		}
-		if(temp->Type=="long long int")
+		else if(temp->Type=="long long int")
 		{
 			temp->data=new long long int;
 			*((long long int *)temp->data)=*((long long int *)SourceTemp->data);
 		}
-		if(temp->Type=="string")
+		else if(temp->Type=="string")
 		{
 			temp->data=new std::string;
 			*((std::string *)temp->data)=*((std::string *)SourceTemp->data);
 		}
-		if(temp->Type=="array")
+		else if(temp->Type=="array")
 		{
 			temp->data=new NasalList;
 			*((NasalList *)temp->data)=*((NasalList *)SourceTemp->data);
 		}
-		if(temp->Type=="hash")
+		else if(temp->Type=="hash")
 		{
 			temp->data=new NasalHash;
 			*((NasalHash *)temp->data)=*((NasalHash *)SourceTemp->data);
 		}
+		else if(temp->Type=="null")
+		{
+			temp->data=NULL;
+		}
 		temp->next=NULL;
 	}
 }
+
 NasalList::~NasalList()
 {
 	ListUnit *temp=head;
@@ -80,19 +86,19 @@ NasalList::~NasalList()
 		{
 			if(temp->Type=="int")
 				delete (int *)temp->data;
-			if(temp->Type=="float")
+			else if(temp->Type=="float")
 				delete (float *)temp->data;
-			if(temp->Type=="double")
+			else if(temp->Type=="double")
 				delete (double *)temp->data;
-			if(temp->Type=="char")
+			else if(temp->Type=="char")
 				delete (char *)temp->data;
-			if(temp->Type=="long long int")
+			else if(temp->Type=="long long int")
 				delete (long long int *)temp->data;
-			if(temp->Type=="string")
+			else if(temp->Type=="string")
 				delete (std::string *)temp->data;
-			if(temp->Type=="array")
+			else if(temp->Type=="array")
 				delete (NasalList *)temp->data;
-			if(temp->Type=="hash")
+			else if(temp->Type=="hash")
 				delete (NasalHash *)temp->data;
 		}
 		delete temp;
@@ -102,19 +108,19 @@ NasalList::~NasalList()
 	{
 		if(temp->Type=="int")
 			delete (int *)temp->data;
-		if(temp->Type=="float")
+		else if(temp->Type=="float")
 			delete (float *)temp->data;
-		if(temp->Type=="double")
+		else if(temp->Type=="double")
 			delete (double *)temp->data;
-		if(temp->Type=="char")
+		else if(temp->Type=="char")
 			delete (char *)temp->data;
-		if(temp->Type=="long long int")
+		else if(temp->Type=="long long int")
 			delete (long long int *)temp->data;
-		if(temp->Type=="string")
+		else if(temp->Type=="string")
 			delete (std::string *)temp->data;
-		if(temp->Type=="array")
+		else if(temp->Type=="array")
 			delete (NasalList *)temp->data;
-		if(temp->Type=="hash")
+		else if(temp->Type=="hash")
 			delete (NasalHash *)temp->data;
 	}
 	delete temp;
@@ -131,45 +137,51 @@ void NasalList::PrintList()
 		{
 			if(temp->Type=="int")
 				std::cout<<*((int *)temp->data)<<", ";
-			if(temp->Type=="float")
+			else if(temp->Type=="float")
 				std::cout<<*((float *)temp->data)<<", ";
-			if(temp->Type=="double")
+			else if(temp->Type=="double")
 				std::cout<<*((double *)temp->data)<<", ";
-			if(temp->Type=="char")
+			else if(temp->Type=="char")
 				std::cout<<"\""<<*((char *)temp->data)<<"\", ";
-			if(temp->Type=="long long int")
+			else if(temp->Type=="long long int")
 				std::cout<<*((long long int *)temp->data)<<", ";
-			if(temp->Type=="string")
+			else if(temp->Type=="string")
 				std::cout<<"\""<<*((std::string *)temp->data)<<"\", ";
-			if(temp->Type=="array")
+			else if(temp->Type=="array")
 			{
 				((NasalList *)temp->data)->PrintList();
 				std::cout<<", ";
 			}
-			if(temp->Type=="hash")
+			else if(temp->Type=="hash")
 			{
 				((NasalHash *)temp->data)->PrintHash();
 				std::cout<<", ";
 			}
+			else if(temp->Type=="null")
+			{
+				std::cout<<"NULL, ";
+			}
 		}
 		else
 		{
 			if(temp->Type=="int")
 				std::cout<<*((int *)temp->data);
-			if(temp->Type=="float")
+			else if(temp->Type=="float")
 				std::cout<<*((float *)temp->data);
-			if(temp->Type=="double")
+			else if(temp->Type=="double")
 				std::cout<<*((double *)temp->data);
-			if(temp->Type=="char")
+			else if(temp->Type=="char")
 				std::cout<<"\""<<*((char *)temp->data)<<"\"";
-			if(temp->Type=="long long int")
+			else if(temp->Type=="long long int")
 				std::cout<<*((long long int *)temp->data);
-			if(temp->Type=="string")
+			else if(temp->Type=="string")
 				std::cout<<"\""<<*((std::string *)temp->data)<<"\"";
-			if(temp->Type=="array")
+			else if(temp->Type=="array")
 				((NasalList *)temp->data)->PrintList();
-			if(temp->Type=="hash")
+			else if(temp->Type=="hash")
 				((NasalHash *)temp->data)->PrintHash();
+			else if(temp->Type=="null")
+				std::cout<<"NULL";
 		}
 	}
 	std::cout<<"]";
@@ -194,37 +206,138 @@ void NasalList::Append(void *AppendData,const char *TypeName)
 		NewListMember->data=new int;
 		*((int *)NewListMember->data)=*((int *)AppendData);
 	}
-	if(TypeName=="float")
+	else if(TypeName=="float")
 	{
 		NewListMember->data=new float;
 		*((float *)NewListMember->data)=*((float *)AppendData);
 	}
-	if(TypeName=="double")
+	else if(TypeName=="double")
 	{
 		NewListMember->data=new double;
 		*((double *)NewListMember->data)=*((double *)AppendData);
 	}
-	if(TypeName=="char")
+	else if(TypeName=="char")
 	{
 		NewListMember->data=new char;
 		*((char *)NewListMember->data)=*((char *)AppendData);
 	}
-	if(TypeName=="long long int")
+	else if(TypeName=="long long int")
 	{
 		NewListMember->data=new long long int;
 		*((long long int *)NewListMember->data)=*((long long int *)AppendData);
 	}
-	if(TypeName=="string")
+	else if(TypeName=="string")
 	{
 		NewListMember->data=new std::string;
 		*((std::string *)NewListMember->data)=*((std::string *)AppendData);
 	}
-	if(TypeName=="array")
+	else if(TypeName=="array")
 	{
 		NewListMember->data=new NasalList;
 		*((NasalList *)NewListMember->data)=TempList;
 	}
-	if(TypeName=="hash")
+	else if(TypeName=="hash")
+	{
+		NewListMember->data=new NasalHash;
+		*((NasalHash *)NewListMember->data)=*((NasalHash *)AppendData);
+	}
+	else if(TypeName=="var")
+	{
+		NewListMember->Type=(*(var *)AppendData).Type;
+		if((*(var *)AppendData).Type=="int")
+		{
+			NewListMember->data=new int;
+			*((int *)NewListMember->data)=*((int *)(*(var *)AppendData).data);
+		}
+		else if((*(var *)AppendData).Type=="float")
+		{
+			NewListMember->data=new float;
+			*((float *)NewListMember->data)=*((float *)(*(var *)AppendData).data);
+		}
+		else if((*(var *)AppendData).Type=="double")
+		{
+			NewListMember->data=new double;
+			*((double *)NewListMember->data)=*((double *)(*(var *)AppendData).data);
+		}
+		else if((*(var *)AppendData).Type=="char")
+		{
+			NewListMember->data=new char;
+			*((char *)NewListMember->data)=*((char *)(*(var *)AppendData).data);
+		}
+		else if((*(var *)AppendData).Type=="long long int")
+		{
+			NewListMember->data=new long long int;
+			*((long long int *)NewListMember->data)=*((long long int *)(*(var *)AppendData).data);
+		}
+		else if((*(var *)AppendData).Type=="string")
+		{
+			NewListMember->data=new std::string;
+			*((std::string *)NewListMember->data)=*((std::string *)(*(var *)AppendData).data);
+		}
+		else if((*(var *)AppendData).Type=="array")
+		{
+			NewListMember->data=new NasalList;
+			*((NasalList *)NewListMember->data)=*((NasalList *)(*(var *)AppendData).data);
+		}
+		else if((*(var *)AppendData).Type=="hash")
+		{
+			NewListMember->data=new NasalHash;
+			*((NasalHash *)NewListMember->data)=*((NasalHash *)(*(var *)AppendData).data);
+		}
+	}
+	NewListMember->next=NULL;
+}
+
+void NasalList::Append(void *AppendData,std::string &TypeName)
+{
+	NasalList TempList;//sometimes user may use n.append(n)
+	if(TypeName=="array")
+		TempList=*((NasalList *)AppendData);
+	ListUnit *temp=head;
+	while(temp->next)
+	{
+		temp=temp->next;
+	}
+	ListUnit *NewListMember=new ListUnit;
+	temp->next=NewListMember;
+	NewListMember->data=NULL;
+	NewListMember->Type=TypeName;
+	if(TypeName=="int")
+	{
+		NewListMember->data=new int;
+		*((int *)NewListMember->data)=*((int *)AppendData);
+	}
+	else if(TypeName=="float")
+	{
+		NewListMember->data=new float;
+		*((float *)NewListMember->data)=*((float *)AppendData);
+	}
+	else if(TypeName=="double")
+	{
+		NewListMember->data=new double;
+		*((double *)NewListMember->data)=*((double *)AppendData);
+	}
+	else if(TypeName=="char")
+	{
+		NewListMember->data=new char;
+		*((char *)NewListMember->data)=*((char *)AppendData);
+	}
+	else if(TypeName=="long long int")
+	{
+		NewListMember->data=new long long int;
+		*((long long int *)NewListMember->data)=*((long long int *)AppendData);
+	}
+	else if(TypeName=="string")
+	{
+		NewListMember->data=new std::string;
+		*((std::string *)NewListMember->data)=*((std::string *)AppendData);
+	}
+	else if(TypeName=="array")
+	{
+		NewListMember->data=new NasalList;
+		*((NasalList *)NewListMember->data)=TempList;
+	}
+	else if(TypeName=="hash")
 	{
 		NewListMember->data=new NasalHash;
 		*((NasalHash *)NewListMember->data)=*((NasalHash *)AppendData);
@@ -243,19 +356,19 @@ NasalList& NasalList::operator=(const NasalList &Source)
 		{
 			if(temp->Type=="int")
 				delete (int *)temp->data;
-			if(temp->Type=="float")
+			else if(temp->Type=="float")
 				delete (float *)temp->data;
-			if(temp->Type=="double")
+			else if(temp->Type=="double")
 				delete (double *)temp->data;
-			if(temp->Type=="char")
+			else if(temp->Type=="char")
 				delete (char *)temp->data;
-			if(temp->Type=="long long int")
+			else if(temp->Type=="long long int")
 				delete (long long int *)temp->data;
-			if(temp->Type=="string")
+			else if(temp->Type=="string")
 				delete (std::string *)temp->data;
-			if(temp->Type=="array")
+			else if(temp->Type=="array")
 				delete (NasalList *)temp->data;
-			if(temp->Type=="hash")
+			else if(temp->Type=="hash")
 				delete (NasalHash *)temp->data;
 		}
 		delete temp;
@@ -296,46 +409,313 @@ NasalList& NasalList::operator=(const NasalList &Source)
 			temp->data=new int;
 			*((int *)temp->data)=*((int *)SourceTemp->data);
 		}
-		if(temp->Type=="float")
+		else if(temp->Type=="float")
 		{
 			temp->data=new float;
 			*((float *)temp->data)=*((float *)SourceTemp->data);
 		}
-		if(temp->Type=="double")
+		else if(temp->Type=="double")
 		{
 			temp->data=new double;
 			*((double *)temp->data)=*((double *)SourceTemp->data);
 		}
-		if(temp->Type=="char")
+		else if(temp->Type=="char")
 		{
 			temp->data=new char;
 			*((char *)temp->data)=*((char *)SourceTemp->data);
 		}
-		if(temp->Type=="long long int")
+		else if(temp->Type=="long long int")
 		{
 			temp->data=new long long int;
 			*((long long int *)temp->data)=*((long long int *)SourceTemp->data);
 		}
-		if(temp->Type=="string")
+		else if(temp->Type=="string")
 		{
 			temp->data=new std::string;
 			*((std::string *)temp->data)=*((std::string *)SourceTemp->data);
 		}
-		if(temp->Type=="array")
+		else if(temp->Type=="array")
 		{
 			temp->data=new NasalList;
 			*((NasalList *)temp->data)=*((NasalList *)SourceTemp->data);
 		}
-		if(temp->Type=="hash")
+		else if(temp->Type=="hash")
 		{
 			temp->data=new NasalHash;
 			*((NasalHash *)temp->data)=*((NasalHash *)SourceTemp->data);
 		}
+		else if(temp->Type=="null")
+		{
+			temp->data=NULL;
+		}
 		temp->next=NULL;
 	}
 	return *this;
 }
 
+void NasalList::SetSize(const int Size)
+{
+	if(Size==0)
+	{
+		ListUnit *temp=head;
+		ListUnit *DeleteNode;
+		temp=temp->next;
+		head->next=NULL;
+		while(temp->next)
+		{
+			DeleteNode=temp;
+			if(temp->data)
+			{
+				if(temp->Type=="int")
+					delete (int *)temp->data;
+				else if(temp->Type=="float")
+					delete (float *)temp->data;
+				else if(temp->Type=="double")
+					delete (double *)temp->data;
+				else if(temp->Type=="char")
+					delete (char *)temp->data;
+				else if(temp->Type=="long long int")
+					delete (long long int *)temp->data;
+				else if(temp->Type=="string")
+					delete (std::string *)temp->data;
+				else if(temp->Type=="array")
+					delete (NasalList *)temp->data;
+				else if(temp->Type=="hash")
+					delete (NasalHash *)temp->data;
+			}
+			temp=temp->next;
+			delete DeleteNode;
+		}
+		if(temp->data)
+		{
+			if(temp->Type=="int")
+				delete (int *)temp->data;
+			else if(temp->Type=="float")
+				delete (float *)temp->data;
+			else if(temp->Type=="double")
+				delete (double *)temp->data;
+			else if(temp->Type=="char")
+				delete (char *)temp->data;
+			else if(temp->Type=="long long int")
+				delete (long long int *)temp->data;
+			else if(temp->Type=="string")
+				delete (std::string *)temp->data;
+			else if(temp->Type=="array")
+				delete (NasalList *)temp->data;
+			else if(temp->Type=="hash")
+				delete (NasalHash *)temp->data;
+		}
+		delete temp;
+		return;
+	}
+	int cnt=0;
+	ListUnit *temp=head;
+	while(temp->next)
+	{
+		temp=temp->next;
+		++cnt;
+		if(cnt==Size)
+		{
+			ListUnit *DeleteNode=temp->next;
+			temp->next=NULL;
+			temp=DeleteNode;
+			while(DeleteNode->next)
+			{
+				DeleteNode=DeleteNode->next;
+				if(temp->data)
+				{
+					if(temp->Type=="int")
+						delete (int *)temp->data;
+					else if(temp->Type=="float")
+						delete (float *)temp->data;
+					else if(temp->Type=="double")
+						delete (double *)temp->data;
+					else if(temp->Type=="char")
+						delete (char *)temp->data;
+					else if(temp->Type=="long long int")
+						delete (long long int *)temp->data;
+					else if(temp->Type=="string")
+						delete (std::string *)temp->data;
+					else if(temp->Type=="array")
+						delete (NasalList *)temp->data;
+					else if(temp->Type=="hash")
+						delete (NasalHash *)temp->data;
+				}
+				delete temp;
+				temp=DeleteNode;
+			}
+			if(temp->data)
+			{
+				if(temp->Type=="int")
+					delete (int *)temp->data;
+				else if(temp->Type=="float")
+					delete (float *)temp->data;
+				else if(temp->Type=="double")
+					delete (double *)temp->data;
+				else if(temp->Type=="char")
+					delete (char *)temp->data;
+				else if(temp->Type=="long long int")
+					delete (long long int *)temp->data;
+				else if(temp->Type=="string")
+					delete (std::string *)temp->data;
+				else if(temp->Type=="array")
+					delete (NasalList *)temp->data;
+				else if(temp->Type=="hash")
+					delete (NasalHash *)temp->data;
+			}
+			delete temp;
+			return;
+		}
+	}
+	while(cnt<Size)
+	{
+		temp->next=new ListUnit;
+		temp=temp->next;
+		temp->Type="null";
+		temp->data=NULL;
+		++cnt;
+	}
+	temp->next=NULL;
+	return;
+}
+NasalList NasalList::SubVec(const int start,const int length=nil)
+{
+	int cnt=-1;
+	ListUnit *temp=head;
+	while(temp->next)
+	{
+		temp=temp->next;
+		++cnt;
+		if(cnt==start)
+		{
+			NasalList NewNasalList;
+			while(temp->next)
+			{
+				NewNasalList.Append(temp->data,temp->Type);
+				temp=temp->next;
+				if(cnt==length)
+					return NewNasalList;
+				++cnt;
+			}
+			if(length!=nil&&cnt<length)
+				std::cout<<"[Error] Length out of range: (length) "<<length<<"|(range) "<<cnt<<"."<<std::endl;
+			NewNasalList.Append(temp->data,temp->Type);
+			return NewNasalList;
+		}
+	}
+	std::cout<<"[Error] Starting place out of range: (start) "<<start<<"|(range) "<<cnt<<"."<<std::endl;
+	NasalList NullList;
+	NullList.SetSize(1);
+	return NullList;
+}
+
+var NasalList::Pop()
+{
+	ListUnit *temp=head;
+	ListUnit *NewLastUnit;
+	while(temp->next)
+	{
+		NewLastUnit=temp;
+		temp=temp->next;
+	}
+	NewLastUnit->next=NULL;
+	var TempVar;
+	TempVar.Type=temp->Type;
+	if(TempVar.Type=="int")
+	{
+		TempVar.data=new int;
+		*((int *)TempVar.data)=*((int *)temp->data);
+	}
+	else if(TempVar.Type=="float")
+	{
+		TempVar.data=new float;
+		*((float *)TempVar.data)=*((float *)temp->data);
+	}
+	else if(TempVar.Type=="double")
+	{
+		TempVar.data=new double;
+		*((double *)TempVar.data)=*((double *)temp->data);
+	}
+	else if(TempVar.Type=="char")
+	{
+		TempVar.data=new char;
+		*((char *)TempVar.data)=*((char *)temp->data);
+	}
+	else if(TempVar.Type=="long long int")
+	{
+		TempVar.data=new long long int;
+		*((long long int *)TempVar.data)=*((long long int *)temp->data);
+	}
+	else if(TempVar.Type=="string")
+	{
+		TempVar.data=new std::string;
+		*((std::string *)TempVar.data)=*((std::string *)temp->data);
+	}
+	else if(TempVar.Type=="array")
+	{
+		TempVar.data=new NasalList;
+		*((NasalList *)TempVar.data)=*((NasalList *)temp->data);
+	}
+	else if(TempVar.Type=="hash")
+	{
+		TempVar.data=new NasalHash;
+		*((NasalHash *)TempVar.data)=*((NasalHash*)temp->data);
+	}
+	else if(TempVar.Type=="null")
+		TempVar.data=NULL;
+	
+	if(temp->data)
+	{
+		if(temp->Type=="int")
+			delete (int *)temp->data;
+		else if(temp->Type=="float")
+			delete (float *)temp->data;
+		else if(temp->Type=="double")
+			delete (double *)temp->data;
+		else if(temp->Type=="char")
+			delete (char *)temp->data;
+		else if(temp->Type=="long long int")
+			delete (long long int *)temp->data;
+		else if(temp->Type=="string")
+			delete (std::string *)temp->data;
+		else if(temp->Type=="array")
+			delete (NasalList *)temp->data;
+		else if(temp->Type=="hash")
+			delete (NasalHash *)temp->data;
+	}
+	delete temp;
+	
+	return TempVar;
+}
+
+void NasalList::Sort(bool _cmp_1,bool _cmp_2)
+{
+	return;
+}
+
+var::~var()
+{
+	if(data)
+	{
+		if(Type=="int")
+			delete (int *)data;
+		else if(Type=="float")
+			delete (float *)data;
+		else if(Type=="double")
+			delete (double *)data;
+		else if(Type=="char")
+			delete (char *)data;
+		else if(Type=="long long int")
+			delete (long long int *)data;
+		else if(Type=="string")
+			delete (std::string *)data;
+		else if(Type=="array")
+			delete (NasalList *)data;
+		else if(Type=="hash")
+			delete (NasalHash *)data;
+	}
+}
+
 }
 
 #endif
diff --git a/nasal_list.h b/nasal_list.h
index b2c066e..b6de14b 100644
--- a/nasal_list.h
+++ b/nasal_list.h
@@ -7,6 +7,11 @@
 
 namespace nasal
 {
+#ifndef nil
+#define nil -1
+#endif
+
+class var;
 
 struct ListUnit
 {
@@ -25,7 +30,24 @@ class NasalList
 		~NasalList();
 		void PrintList();
 		void Append(void *,const char *);
+		void Append(void *,std::string &);
 		NasalList& operator=(const NasalList &);
+		void SetSize(const int);
+		NasalList SubVec(const int,const int);
+		var Pop();
+		void Sort(bool,bool);
+};
+
+class var
+{
+	public:
+		std::string Type;
+		void *data;
+		var()
+		{
+			data=NULL;
+		}
+		~var();
 };
 
 }