rb_define_class_id_under  694 class.c            return rb_define_class_id_under(outer, rb_intern(name), super);
rb_define_class_id_under  195 include/ruby/intern.h VALUE rb_define_class_id_under(VALUE, ID, VALUE);
rb_define_class_id_under  276 struct.c           return rb_define_class_id_under(super, id, super);