It seems that we focused on different things. I was talking about the example I have given for arithmetic evaluation. And you focused the AST-based evaluation, which, I belive, is different from my example. I also agree that they called the functions for the same number of times, the difference is how they are called.
Resursive function is a function called itself. Am I wrong? I'm sure the code in my example is recursive. As I have said, you may show those codes I gave as example to somebody know C++ well to check if it is recursive. Best regards, Limin __________________________________ Do you Yahoo!? Read only the mail you want - Yahoo! Mail SpamGuard. http://promotions.yahoo.com/new_mail -- http://mail.python.org/mailman/listinfo/python-list