C++, "too few arguments in function call" error?

[rob@encodia.biz]

Hi all,

I'm using GDB 6.1 on Mac OS X to debug a C++ program.  Occasionally,  
when I try to call an object's member function I get this error:

(gdb) p set1.begin()
too few arguments in function call

In this case "set1" is an STL std::set, but I get the same message  
sometimes with my own classes.  Has anyone seen this before, or know  
what's going on, or a way around it?

thanks,

Rob