DECLARE_SCHEME_CALLBACK (brew_chord_bracket, (SCM));
DECLARE_SCHEME_CALLBACK (width_callback, (SCM,SCM));
static bool has_interface (Grob*);
DECLARE_SCHEME_CALLBACK (brew_chord_bracket, (SCM));
DECLARE_SCHEME_CALLBACK (width_callback, (SCM,SCM));
static bool has_interface (Grob*);