(,ly:dir? . "direction")
(,ly:dispatcher? . "dispatcher")
(,ly:duration? . "duration")
- (,ly:event? . "event")
+ (,ly:event? . "post event")
(,ly:font-metric? . "font metric")
(,ly:grob? . "graphical (layout) object")
(,ly:grob-array? . "array of grobs")