\arpeggioUp with connected voices

[Arjan Bos]

Dear List,

Could anyone please tell me how I can do an arrowed arpeggio with  
\arpeggioUp when two voices share the arpeggio?
I've tried this (adjusted from <http://lilypond.org/doc/v2.11/Documentation/user/lilypond/Arpeggio#Arpeggio 
>):

\version "2.11.39"
\score {
  \new StaffGroup {
    \set Score.connectArpeggios = ##t
    <<
      \new Voice \relative c' {
        \arpeggioUp
        <e g>4\arpeggio
      }
      \new Voice  \relative c {
        \clef bass
        \arpeggioUp
        <c e>4\arpeggio
      }
    >>
  }
  \layout {
    \context {
      \Score
      \consists "Span_arpeggio_engraver"
    }
  }
}

but that gives an unarrowed arpeggio:

arpeggioUp.pdf
Description: Adobe PDF document

Thanks,
A.J.


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