simple scheme function #{ $note #}

[Gianmaria Lari]

Sorry to bother with a simple question. Why this does not work?

\version "2.19.81"

pit = #(define-music-function 

        (p) (ly:pitch?)

        #{ $p #}

        )

{ \pit c' }

Changing the body to

 #{ $p $p #}

or 

#{ $pit 4 #}  

or

#{ $p a' #}

it works....

g.