Grob*me = unsmob_grob (smob);
Real ss = Staff_symbol_referencer::staff_space (me);
SCM size = me->get_property ("bar-size");
- if (is_number (size))
+ if (ly_c_number_p (size))
return scm_make_real (ly_scm2double (size)*ss);
else if (Staff_symbol_referencer::get_staff_symbol (me))
{