Re: Error in resolving number of staff lines

[Marc Hohl]

Am 22.06.2012 10:29, schrieb David Kastrup:
> Marc Hohl <address@hidden> writes:
>
> > Hello list,
> >
> > the following snippet prints a value of 5 in both cases,
> > whereas the second system has
> > only four staff lines. What's wrong here?
> >
> > Regards,
> >
> > Marc
> >
> > \version "2.15.41"
> >
> > #(define (test-bar-print grob)
> >     (let* ((staff-symbol (ly:grob-object grob 'staff-symbol))
> >            (line-count (if (ly:grob? staff-symbol)
> >                            (ly:grob-property staff-symbol 'line-count)
> >                            0)))
> >            (display "\nNumber of staff lines: ")
> >            (display line-count)
> >            (ly:bar-line::print grob)))
>
> > \new Staff {
> >    \override Staff.StaffSymbol #'line-positions = #'(-2 0 2 4)
> >    s1 \bar ":|"
> > }
> You are only overriding line-positions.  While the bar line printer will
> see that this now contains a value and heeds it, this does not magically
> affect the (now ignored) line-count property.
Ah, I see, thanks for the explanation.
But why are the dots placed as if there were only four lines?
If the line number is still 5 and the routine in lily/bar-line.cc
works as expected, why are the dots placed correctly?

(This is associated to 
http://lists.gnu.org/archive/html/lilypond-devel/2012-06/msg00310.html)

Regards,

Marc