static SCM get_spacing_spec (Grob *before, Grob *after, bool pure, int start, int end);
static Real get_fixed_spacing (Grob *before, Grob *after, int spaceable_index, bool pure, int start, int end);
static SCM get_spacing_spec (Grob *before, Grob *after, bool pure, int start, int end);
static Real get_fixed_spacing (Grob *before, Grob *after, int spaceable_index, bool pure, int start, int end);