ly:run-translator

[Timothy Lanfear]

I am working on an engraver to modify line-breaking near double bars by 
adjusting line-break-penalty at double bars and bars just before and 
just after. The idea is to process music with ly:run-translator to 
locate the bars in question and then adjust line-break-penalty for the 
identified bars with a second pass. I will ask about the engraver later 
once the initial questions about ly:run-translator are resolved.

Unsurprisingly, I encounter the same issues as Jan-Peter, 
http://lilypond.1069038.n5.nabble.com/using-run-translator-td202249.html 
and 
http://lilypond.1069038.n5.nabble.com/crash-running-translator-td216130.html. 
It seems these can be fixed by scorifying the music as suggested by 
David K, and setting fonts and output-scale in the layout block. Does 
this make sense? And have I missed anything?

\version "2.20.0"

music = {
  \time 6/8
  r4. r4.
  c''4. ~ 4.
}

mylayout = \layout {
  fonts        = #(ly:output-def-lookup $defaultpaper 'fonts)
  output-scale = #(ly:output-def-lookup $defaultpaper 'output-scale)
}

#(ly:run-translator (ly:score-music (scorify-music music)) mylayout)

--
Timothy Lanfear, Bristol, UK.