Re: Putting a \layout block in a Scheme macro

[Timothy Lanfear]

On 27/01/17 19:20, Jérôme Plût wrote:
> Thanks for the answer, but:
>
> your code produces a failed assertion in the lilypond binary:
>
> lilypond: 
> /home/gub/NewGub/gub/target/linux-x86/src/lilypond-git.sv.gnu.org--lilypond.git-release-unstable/lily/book.cc:258:
>  void Book::process_score(SCM, Paper_book*, Output_def*): Assertion `0' failed.
>
> This assertion is unclear but, looking at the source file, it
> obviously means that the top-level book content was neither a Score
> nor a markup list (the execution path seems to go ly:book-process ->
> Book::process -> Book::process_score). I leave it to the experts from
> there!

All I can say is that it works perfectly for me. I'm using the pre-built 
binary for 2.19.54, Ubuntu 16.04. 64-bit.

> And while we are there: your solution seems to create a new book for
> the score. Is that the case? How would one adapt it to incorporate the
> score at top-level?

Here is a solution that returns a score from Scheme.

\version "2.19.54"

BlankStaff =
#(define-scheme-function (count) (integer?)
  (let* ((blankstaff #{ \score { \repeat unfold #count { s1 \break } } #} )
         (layout     #{ \layout { \context { \Staff \remove 
"Bar_engraver" } } #} ))
    (ly:output-def-set-variable! layout 'indent (ly:mm 0))
    (ly:output-def-set-variable! layout 'ragged-right #f)
    (ly:score-add-output-def! blankstaff layout)
    blankstaff
))

\BlankStaff 4


--
Timothy Lanfear, Bristol, UK.