diff --git a/version2.0/abstract_syntax_tree.h b/version2.0/abstract_syntax_tree.h
index a015db7..aef6696 100644
--- a/version2.0/abstract_syntax_tree.h
+++ b/version2.0/abstract_syntax_tree.h
@@ -104,7 +104,7 @@ void abstract_syntax_tree::print_tree(const int n)
 	std::cout<<std::endl;
 	if(!children.empty())
 	{
-		for(auto i=children.begin();i!=children.end();++i)
+		for(std::list<abstract_syntax_tree>::iterator i=children.begin();i!=children.end();++i)
 			i->print_tree(n+1);
 	}
 	return;
diff --git a/version2.0/nasal_lexer.h b/version2.0/nasal_lexer.h
index 7186d58..d99adf0 100644
--- a/version2.0/nasal_lexer.h
+++ b/version2.0/nasal_lexer.h
@@ -134,7 +134,7 @@ class resource_file
 			std::cout<<line<<"\t";
 			for(std::list<char>::iterator i=tmp.begin();i!=tmp.end();++i)
 			{
-				if(32<=*i && *i<128)
+				if(32<=*i)
 					std::cout<<*i;
 				else
 					std::cout<<" ";
diff --git a/version2.0/numeral_misc.h b/version2.0/numeral_misc.h
index f9b9386..886a697 100644
--- a/version2.0/numeral_misc.h
+++ b/version2.0/numeral_misc.h
@@ -19,7 +19,7 @@ bool check_numerable_string(std::string str)
 	{
 		int str_len=str.length();
 		for(int i=2;i<str_len;++i)
-			if(!('0'<=str[i] && str[i]<='9' || 'a'<=str[i] && str[i]<='f' || 'A'<=str[i] && str[i]<='F'))
+			if(!(('0'<=str[i] && str[i]<='9') || ('a'<=str[i] && str[i]<='f') || ('A'<=str[i] && str[i]<='F')))
 				return false;
 		return true;
 	}