#include <iostream>
#include <sstream>
#include <string>
+#include <cstdio>
namespace GiNaC {
// Skip any whitespace.
c = skipspace(input, c, line_num);
- // identifier: [a-zA-Z][a-zA-Z0-9]*
+ // identifier: [a-zA-Z][a-zA-Z0-9_]*
if (isalpha(c)) {
str = c;
do {
c = input->get();
- if (isalnum(c))
+ if ( isalnum(c) || c=='_' )
str += c;
else
break;