scheme function containing score {...}

[Gianmaria Lari]

I'm trying to put the score functionality inside a function (consider it a test). Here it is the code:

\version "2.19.80"

myScore = 

#(define (music) (ly:music?) #{

  \score {

    $music

    \layout{}

    \midi{}

   } #} )

\myScore {a b c'}

The code correctly generate a score but it does not generate the midi file. Why???

I'm using Frescobaldi.

Thank you, g.