Re: is MultiMeasureRest breakable?

[Kieren MacMillan]

Hi Keith,

>> Is there a way to break MultiMeasureRests in the voice, so that
>> the piano part is spaced "naturally" (as
>> opposed to breaking the piano part in order to fit the voice's MMRs)?
> 
> Possibly nobody understands the context.

Good point.
I was wondering why my last few posts have received no responses from this 
normally responsive list — I never doubted it was my fault!  :)

> Multi-measure rests are always breakable.
> theVoice = {R1* 7}
> \score {{\time 7/4 \theVoice}} % printed as four bars of rest

What I mean is, if the barline in another [polymetric] staff falls in the 
middle of a MultiMeasureRest, could Lilypond [automatically] split the measure, 
perhaps putting a parenthesized MMR on the following system? The following 
snippet shouldn't have to run off the end of the page, since there are ample 
opportunities to put a system break:

\version "2.17"
\language "english"

\layout {
  \context {
    \Score
    \remove "Timing_translator"
    \remove "Default_bar_line_engraver"
  }
  \context {
    \Staff
    \consists "Timing_translator"
    \consists "Default_bar_line_engraver"
  }
}

theVoice = {
  \time 4/4
  R1*7 
}

thePiano = \relative c' {
  \time 7/8
  \repeat "unfold" 56 { c8 }
}

\score {
  <<
    \new Staff \theVoice
    \new Staff \thePiano
  >>
}

It would be great if I could (e.g.) \override MultiMeasureRest.breakable = ##t, 
and it would end up like this (but with the after-line-breaking MMR 
parenthesized):

\version "2.17"
\language "english"

\layout {
  \context {
    \Score
    \remove "Timing_translator"
    \remove "Default_bar_line_engraver"
  }
  \context {
    \Staff
    \consists "Timing_translator"
    \consists "Default_bar_line_engraver"
  }
}

theVoice = {
  \time 4/4
  \repeat "unfold" 7 { R1*1/8 \repeat "unfold" 7 { \bar "" s8 } } 
}

thePiano = \relative c' {
  \time 7/8
  \repeat "unfold" 56 { c8 }
}

\score {
  <<
    \new Staff \theVoice
    \new Staff \thePiano
  >>
}

I could do this manually (or set up a function), but I was just wondering if 
Lily had it in her to do this automagically…  =)

Thanks,
Kieren.