Re: Four Bars per Line/System, again :)

[Jay Anderson]

Slightly better would be to get rid of the bars-per-line define so
it's self-contained:

#(define (line-break-every-nth-engraver bars-per-line)
  (lambda (context)
     (make-engraver
       (acknowledgers ((paper-column-interface engraver grob source-engraver)
         (let ((current-bar (ly:context-property context 'currentBarNumber)))
           (if (= (remainder current-bar bars-per-line) 1)
               (if (eq? #t (ly:grob-property grob 'non-musical))
                   (set! (ly:grob-property grob 'line-break-permission) 'force)
                   (set! (ly:grob-property grob 'line-break-permission) 
'())))))))))

...

\layout {
  \context {
    \Score
    %% the following line necessary if you want to put more
    %% measures to a line than Lily wants to allow
    \override NonMusicalPaperColumn #'line-break-permission = ##f
    \consists #(line-break-every-nth-engraver 4)
  }
}

-----Jay