relative music inside music functions explodes when used twice

[Janek Warchoł]

Hi,

i have a function that takes music as an argument and uses it twice - each time with a different tag appended, so that later on i can decide what to output:

voiceDivisi =

#(define-music-function (parser location m1 m2) (ly:music? ly:music?)

   #{

     \tag divI \context Voice = "divI" { #m1 }

     \tag divII \context Voice = "divII" { #m2 }

     \tag together \context Voice = "both" << #m1 #m2 >>

   #})

The problem is that when used with relative mode, the output gets crazy:

music = \relative c' {

  \voiceDivisi {

    c4 d e f

  }

  {

    e4 f g a

  }

}

\new Staff \keepWithTag divI \music

\new Staff \keepWithTag divII \music

\new Staff \keepWithTag together \music

(see attachment)

I have checked that the problem disappears when the function uses the arguments (m1 and m2) only once.  Is this a bug?  Can i work around it, or maybe i should be doing this in an altogether different way?

best,

Janek

exploding octaves.png
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