Re: Questions about using Scheme with Lilypond

[Aaron Hill]

On 2020-11-16 10:28 am, Tom Brennan wrote:
> Re: arity, the (admittedly unclear) question wasn't whether or not 
> scheme
> supports multi-arity, but whether you can "splat" any list (doesn't 
> have to
> be from args), into a block of lilypond code, i.e.,

The list splicing operators [1] are likely what you need to use:

[1]: 
http://lilypond.org/doc/v2.21/Documentation/extending-big-page.html#importing-scheme-in-lilypond

%%%%
\version "2.20.0"

foo = #(music-pitches #{ b' g' a' #})
{ g'4. #@(map (lambda (p) #{ $p 8 #}) foo) b'4 $@(reverse foo) 2 }
%%     \_________________________________/     \_____________/
{ g'4.             b'8 g'8 a'8             b'4     a' g' b'    2 }
%%%%

While the above deals with a list of pitches, here is another example 
involving scores:

%%%%
\version "2.20.0"

baz = #(list #{ \score { { b'1 } } #}
             #{ \score { { g'4 a'2. } } #}
             #{ \score { { b'4. g'8 a'2 } } #})
\bookpart { $@baz }

#(define (score->markup score)
  #{ \markup \score { #score \layout { indent = 0 } } #})
\markup { Lorem ipsum #@(map score->markup baz) dolor sit amet. }
%%%%


-- Aaron Hill