newbie question on scheme functions

[Andrea Rossato]

Hi there!

I've recently discovered LilyPond and I'm really impressed by it! Great job!

Just a newbie question.
I need to be able to change the output of chords' names to the Italian 
ones (Do instead of C, and so on).
The only viable solution I was able to find is to hack 
scm/chord-name.scm and add:
(define-public (note-name->italian-markup pitch)
  "Return Italian pitch markup for PITCH."
  (make-line-markup
   (list
    (make-simple-markup
     (vector-ref #("Do" "Re" "Mi" "Fa" "Sol" "La" "Si") 
(ly:pitch-notename pitch)))
     (accidental->markup (ly:pitch-alteration pitch)))))

and, in my .ly files, add, in the ChordName context:
\set chordRootNamer = #note-name->italian-markup

I'm trying to find a cleaner solution: is it possible to define that 
function inside a .ly file?

I tried, by adding a # before the definition,  but I get an error message.

I'm new to lilypond, and to scheme. Could you give me some directions to 
get a better understanding of the lilypond internal (unfortunately the 
manual seems not to be a viable solution at my present knowledge level).
Than you
Andrea