static bool has_interface (Grob*) ;
static void add_support (Grob*,Grob*);
static void add_staff_support (Grob*);
static Direction get_direction (Grob*);
static bool has_interface (Grob*) ;
static void add_support (Grob*,Grob*);
static void add_staff_support (Grob*);
static Direction get_direction (Grob*);