2.7.31 over troubles

[Martial]

hello 
(in win2k) 
1) the compiled time is over long 

2) Nous  give out N°us :-)) 

3 ) Parsing...ERROR: Unbound variable: Note_head::print
    with this macro 
%------NOTES PARENTHESES---
#(define (parenthesize-callback callback)
   (define (parenthesize-stencil grob)
     (let* ((fn (ly:grob-default-font grob))
            (pclose (ly:font-get-glyph fn "accidentals.rightparen"))
            (popen (ly:font-get-glyph fn "accidentals.leftparen"))
            (subject (callback grob))

                ; get position of stem
                (stem-pos (ly:grob-property grob 'stem-attachment))
                
            ; remember old size
            (subject-dim-x (ly:stencil-extent subject 0))
            (subject-dim-y (ly:stencil-extent subject 1)))

        ;; add parens
        (set! subject
             (ly:stencil-combine-at-edge 
              (ly:stencil-combine-at-edge subject 0 1 pclose 0)
              0 -1 popen  0))
                  
                ; adjust stem position
                (ly:grob-set-property! grob 'stem-attachment
                        (cons (- (car stem-pos) 0.43) (cdr stem-pos)))

        ; adjust size
       (ly:make-stencil
        (ly:stencil-expr subject)
                  (cons (- (car subject-dim-x) 0.5) (+ (cdr
subject-dim-x) 0.5)) subject-dim-y)))
   parenthesize-stencil)


parenthesOn =  \override NoteHead #'stencil = 
#(parenthesize-callback Note_head::print) 
parenthesOff =  \revert NoteHead #'stencil
%---------------------------------------------

Regards