DECLARE_SCHEME_CALLBACK (percent, (SCM));
static void add_column (Grob *, Item *);
DECLARE_SCHEME_CALLBACK (set_spacing_rods, (SCM));
DECLARE_SCHEME_CALLBACK (percent, (SCM));
static void add_column (Grob *, Item *);
DECLARE_SCHEME_CALLBACK (set_spacing_rods, (SCM));