DECLARE_SCHEME_CALLBACK (print, (SCM));
DECLARE_SCHEME_CALLBACK (height, (SCM));
DECLARE_SCHEME_CALLBACK (calc_style, (SCM));
DECLARE_SCHEME_CALLBACK (print, (SCM));
DECLARE_SCHEME_CALLBACK (height, (SCM));
DECLARE_SCHEME_CALLBACK (calc_style, (SCM));