Re: Resolving "cannot resolve rest collision: rest direction not set" warnings

[Jim Long]

On Wed, Dec 19, 2012 at 08:44:29AM +0100, Arle Lommel wrote:
> Hi all, I am working on the same score that spawned discussion about stem 
> lengths and now have another, hopefully less controversial, question.
> 
> I keep getting warnings like the following when I run Lilypond:
> 
> warning: cannot resolve rest collision: rest direction not set

I've run into this or a similar problem before.

Cultivate the habit of using separate, explicit voice constructs:

    \new Voice = "upper" \relative c'' {
      ...
    } % upper voice
    \new Voice = "lower" \relative c'' {
      ...
    } % lower voice

A layman's paraphrase of the error message might be that, while
you are manipulating stem directions and pitched rests to
*simulate* the appearance of separate voices, Lily cannot
reliably determine which voice(s) the rests belong to.

HTH,

Jim