How does map-some-music work?

[Jay Vara]

I am trying to display all the names that appear in a piece of music 
(NoteEvent etc.) using map-some-music. It the function musShow is only 
printing the top level name. What am I missing here?

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\version "2.18.2"
#(define (showMus music) (display-scheme-music (ly:music-property music 
'name "Not Defined")))

musShow = #(define-music-function (parser location myx ) (ly:music?)
            (map-some-music
             (lambda (evt)  (showMus evt )) myx)
            #{ #})


music =  {c ~ c}


\musShow #music
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