scheme function help

[Stjepan Horvat]

I'm trying to figure out how and learn to create a function based on a \displayMusic function.

for example:

\displayMusic { \mark "A" c'4 }

gives me

(make-music

  'SequentialMusic

  'elements

  (list (make-music (quote MarkEvent) (quote label) "A")

        (make-music

          'NoteEvent

          'duration

          (ly:make-duration 2 0 1)

          'pitch

          (ly:make-pitch 0 0 0))))

so what i have gotten so far is that there is new (make-music (quote MarkEvent) (quote label) "A") or (make-music 'MarkEvent 'label "A") in front of c'

and i don't know how to put this line into it. I understand that i have to use cons on 'elements to put the line in front of c.

Is there a way to figure out what "elements" do i have to use in my function to work.

I'm going through http://lilypond.org/doc/v2.12/Documentation/user/lilypond/Music-properties#Music-properties to get an idea of how to get into it but #(display-scheme-music (first (ly:music-property someNote 'elements))) doesn't work. I get an error saying:

Wrong type argument in position 1 (expecting Music): #<Pitch c' > with someNote = c'.

Help would be appreciated.

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Nesmotren govori kao da mačem probada, a jezik je mudrih iscjeljenje. Izreke 12:18