static SCM calc_common (Grob *, Axis);
static Real minimum_distance (Grob *, Grob *, Axis);
static SCM calc_maybe_pure_staff_staff_spacing (Grob *, bool, int, int);
static SCM calc_common (Grob *, Axis);
static Real minimum_distance (Grob *, Grob *, Axis);
static SCM calc_maybe_pure_staff_staff_spacing (Grob *, bool, int, int);