Re: Unconventional score and unwanted stray staff lines

[Thomas Morley]

Am Di., 21. Mai 2019 um 02:32 Uhr schrieb Thomas Morley
<address@hidden>:
>
> Am So., 19. Mai 2019 um 20:32 Uhr schrieb Urs Liska <address@hidden>:
>
> > The staves that continue to be printed appear to only happen when the
> > last note in that staff is an actual printed note. If it's a rest or a
> > space then the extra staves are not printed. Further experimentation
> > and it looks like the extra staves are only printed if the final note
> > is less than a quarter note (!).
> [..]
> > Maybe something to do with the time signature as well?
> >
> > This looks like a bug maybe?
> >
> > I could confirm that behaviour with the following MWE:
> >
> > \version "2.21.0"
> >
> > \score {
> >   <<
> >     \new Staff { c'1 c'1 }
> >     \new Staff { c'1 c'4 c'16 }
> >     \new Staff { c'1 c'8 }
> >     \new Staff { c'1 c'4 }
> >     \new Staff { c'1 c'4. }
> >   >>
> > }
> >
> > I too find this surprising. I suggest you ask on lilypond-user whether this 
> > is a bug or intended behaviour. If it is intended (due to some engraving 
> > convention for example) it might be made configurable.
>
> Looks like a bug to me.
>
> First bad commit:
>
> commit 9ff88d127acb371435a96e04cba7f0e3f525496d
> Author: Keith OHara <address@hidden>
> Date:   Sat Aug 6 12:05:59 2011 -0700
>
>     auto-beam-engraver: keep a Context_handle to starting Staff
>
> Which is in version 2.15.9
>
> cc-ing Keith
>
>
> Cheers,
>   Harm

At least in the minimal one can workaround with inserting \noBeam:

\score {
  <<
    \new Staff { c'1 c'1 }
    \new Staff { c'1 c'4 c'16 \noBeam }
    \new Staff { c'1 c'8 \noBeam }
    \new Staff { c'1 c'4 }
    \new Staff { c'1 c'4. }
  >>
}

Cheers,
  Harm