Re: Engraver not getting an event

[Aaron Hill]

On 2019-04-02 4:26 am, David Kastrup wrote:
> Aaron Hill <address@hidden> writes:
> > Where have I gone wrong in my thinking?
>
> _Either_ the Event_chord_iterator _or_ the Rhythmic_music_iterator are
> doing the broadcasting of note events, depending on whether the notes
> are within a chord or not.  _Only_ the Rhythmic_music_iterator
> broadcasts articulations, so they are _only_ removed and broadcast for
> non-chord notes, and actually only if there is a listener for them,
> otherwise they are kept on the rhythmic event like articulations on
> chord notes _always_ are.

Huh, I was so sure I saw recursion in the broadcasting of events.  I 
need more coffee and/or sleep.  :/

Out of curiosity, how does Lilypond decide which iterator-ctor to 
consult and instanciate?  Is it something like the outer container of 
EventChord trumping the contained NoteEvents?  But then why does the 
same not apply to SimultaneousMusic or SequentialMusic?

> If you want to do anything with chord note articulations, you have to
> listen for the chord notes and look at their articulations property.

Is there a best practice between listening for events vs. acknowledging 
grobs?  I noticed that New_fingering_engraver--which needs to handle 
articulations within chords--opts to acknowledge rather than listen.

Also, it does seem that special care would need to be taken to unify the 
results of handling events that are broadcast vs. the ones that need to 
be wrestled from the clutches of chords.  Or, would it be more 
appropriate (read: sane) to never listen directly to such post-events 
and instead just listen for the rhythmic-events, querying their 
articulations as appropriate?  (The latter seems like it could be 
inefficient.)


-- Aaron Hill