Re: Accidental style in presence of mid-bar line breaks.

[Richard Shann]

On Thu, 2018-06-28 at 09:09 +0100, Richard Shann wrote:
> On Wed, 2018-06-27 at 17:00 +0200, Simon Albrecht wrote:
> > On 26.06.2018 09:11, Richard Shann wrote:
> > > In this connection, I noticed that LilyPond skips printing the
> > > bar
> > > number at the beginning of each line if the bar is being split
> > > over
> > > a
> > > line.
> > 
> > That’s configurable:
> > 
> > %%%%%%%%%%%%%%%%%%%%%%%
> > \version "2.19.80"
> > 
> > \layout {
> >    \context {
> >      \Score
> >      barNumberVisibility = #(every-nth-bar-number-visible 1)
> >      \override BarNumber.break-visibility = #begin-of-line-visible
> >    }
> > }
> > 
> > {
> >    1 2 \bar "" \break 2
> > }
> > %%%%%%%%%%%%%%%%%%%%%%%
> > 
> 
> Thanks - that's useful, I've added it to Denemo's "Allow breaks at
> half
> bar" command. It also suggests that if I look for where the
> parenthesized measure numbers are generated in LilyPond's sources I
> might be able to trigger a warning to the user that a bar has been
> broken, and they (or Denemo) can look for possible repeat accidentals
> to add.

I've had a go at finding where the "(" is added to the bar number
markup and found that 

\version "2.19.43"

#(define-public ((every-nth-bar-number-visible n) barnum mp)
   (display "\n\n\nhello\n\n\n")
  (= 0 (modulo barnum n)))

\layout {
   \context {
     \Score
     barNumberVisibility = #(every-nth-bar-number-visible 1)
     \override BarNumber.break-visibility = #begin-of-line-visible
   }
}

{
   a1 a2 \bar "" \break a2
}

Does issue "hello" on standard out, so I could issue a warning there,
but the only place the "(" seems to be added is at

(define-public (robust-bar-number-function ...)

in scm/translation-functions.scm 

and this procedure does *not* seemed to be called in compiling that
example. Anyone any clues about where in the source code the "(" is
added to a bar numbering?

Richard