class Object_key_undumper;
class Open_type_font;
class Output_property;
-class Page;
class Pango_font;
class Paper_book;
class Paper_column;
class Piano_bar_engraver;
class Pitch;
class Pitch_squash_engraver;
+class Prob;
class Property_iterator;
class Rational;
class Relative_octave_music;