[Issac Trotts]:
> void rb_define_method _((VALUE,const char*,VALUE(*)(),int));
> 
> Why isn't this just
> 
> void rb_define_method (VALUE,const char*,VALUE(*)(),int);
> 
> What does _( ... ) mean?

It's a macro defined in ruby.h

#ifdef HAVE_PROTOTYPES
# define _(args) args
#else
# define _(args) ()
#endif

It allows to ruby.h to work with old and new compilers.

// Niklas