On 19/05/2024 20:27, Carolyn Beeton wrote:
I would like to include some Staff and Voice context settings in the \midi
block only if a flag is set to ##t and I have not been able to figure out how
to do this. When I try to wrap the \context blocks in a code block with #{…#}
I get this error:
trackPerVoiceMWE.ly:31:16: error: syntax error, unexpected '{', expecting
SCM_IDENTIFIER or SCM_TOKEN or STRING or SYMBOL
\context {
Is there any way to conditionally change the Staff_performer based on a flag
setting?
I think this does what you want.
\version "2.24.0"
\include "english.ly" TrackPerVoice = ##t nostaffmidi =
#(define-scheme-function () () (if TrackPerVoice #{ \context { \Staff
\remove "Staff_performer" } #})) voicemidi = #(define-scheme-function ()
() (if TrackPerVoice #{ \context { \Voice \consists "Staff_performer" }
#})) global = { \key c \major \time 4/4 } \score { \new ChoirStaff <<
\new Staff << \new Voice = "soprano" << \global \relative c' { c'4 d e f
<< g1 \\ { g4 f e2 } >> } >> \new Voice = "alto" << \global \voiceTwo
\relative c' { c'4 b a g | f e d2 } >> >> >> \layout {} \midi {
#(ly:message "TrackPerVoice is ~a\n" TrackPerVoice) #(when TrackPerVoice
(ly:message "One track per Voice (may make too many voices with
polyphony)") (ly:message "Turn this off to get sop and alto combined in
one track.")) \nostaffmidi \voicemidi }
Although, I don't understand why the contents of the scheme functions
cannot be placed directly into the midi block like this
\midi { #(if TrackPerVoice #{ \context { \Staff \remove
"Staff_performer" } #}) #(if TrackPerVoice #{ \context { \Voice
\consists "Staff_performer" } #}) }
--
Timothy Lanfear, Bristol, UK.
