Re: Issue 1228 in lilypond: \override RestCollision #'positioning-done = #merge-rests-on-positioning

[lilypond]

Comment #6 on issue 1228 by address@hidden: \override RestCollision  
#'positioning-done = #merge-rests-on-positioning
http://code.google.com/p/lilypond/issues/detail?id=1228

I did get one 'programming error' initially

---snip---
Drawing systems...
programming error: unknown grob in dot col support
continuing, cross fingers
---snip---

It didn't affect my output - the rests were still merged. However I  
couldn't work out where this was occurring to make a small enough snippet  
to test.

But my construct of my main .ly file is

\version "2.13.40"

\include "merge-rests.ly"

Music1 = { .... } % this has the \mergeRestsOn set

Music2 = { .... }

Score {
  \relative c' {
    << { \Music1 } \\ { Music2 } >>
  }
}

When I moved the \relative to each music expression such that

\include "merge-rests.ly"

Music1 = \relative c' { ... } % this has the \mergeRestsOn set
Music2 = \relative c' { ... }

Score {
  << { \Music1 } \\ { Music2 } >>
}

The error went away.

After I sorted out my relative notes (because I had moved the \relative it  
caused a few notes to rearrange and needed some editing) I then couldn't  
get the error even when I put back the \relative.

So I don't know if this something that can be easily diagnosed.