Re: Display the name of the staff of a note/rest/chord/skip-event

[Thomas Morley]

Am Sa., 30. Nov. 2019 um 19:43 Uhr schrieb Paolo Prete <address@hidden>:
>
> Hello,
>
> given a note/rest/chord/skip-event is there a way to display the name of its 
> staff? I need to check if it belongs to staff "UP" or "DOWN" of a piano-staff.
> What if I use map-some-music() function?
>
> %%%%%%%%%%%%%%%%
>
>       (map-some-music (lambda (evt)
>          (let ((name (ly:music-property evt 'name)))
>            (cond
>              ((or (eq? name 'NoteEvent )(eq? name 'EventChord) (eq? name 
> 'RestEvent ) (eq? name 'SkipEvent ))
>
>                 %%%%%%%  (display ?????) %%%%%%%%%
>
>                 evt)
>              (else #f)))) ; => #f = continue, go deeper
>       music)
>
> %%%%%%%%%%%%%%%%
>
> Thanks.

There are not many methods to access context and grob at the same time.
\applyOutput is one of them

printStaffID =
    \applyOutput
      Staff.NoteHead
      #(lambda (grob ctx c) (pretty-print (ly:context-id c) ))

musI = { c1 \printStaffID d }

\new Staff = "foo" \musI

musII = { c1 \change Staff = "up" \printStaffID d }

\new PianoStaff <<
  \new Staff = "up" s1*2
  \new Staff = "down"  \musII
>>

HTH,
  Harm