Re: arbitrary repeat counter

[Simon Bailey]

Hi,

On Wed, 1 Jun 2022 at 17:09, Jean Abou Samra - jean at abou-samra.fr
<mailforwards@cloudmails.net> wrote:
> What did not work? This is perfectly valid Scheme:
>
> (set! count (1+ count))

(set! counter (+ counter 1))

was giving an error message. Probably had some misaligned parentheses
or other weirdness. I didn't know about (1+ var) ;)

> You're welcome. To be honest, and simplifying a bit, I had a
> year of unsuccessful attempts to grasp Scheme before Urs'
> Scheme tutorial made me learn as much of Scheme in 4 hours
> as I had learnt in a year, then another year without that kind
> of help to learn LilyPond internals, so if I've managed to write
> something that is similarly turning a year into 4 hours for
> you, I'm quite happy.

Your readthedocs thing really helped; I still need to have a look at
Urs' tutorial. I did some functional programming sometime at the
beginning of the millenium, but 20yrs of OOP is a hard habit to break
;-)

A further definition:

repeatCountingWithTags = #(define-music-function (n music) (index? ly:music?)
  #{
    <<
      \tag #'score \repeat unfold #n { #music }
      \tag #'part \repeatCounting #n { #music \bar "!|" }
    >>
  #})

ebass = \relative c {
  \clef bass
  \time 7/4
  \repeatCountingWithTags 4 { c4. 8 r4 8 r c2. | d4. 4. 4 e2. | 1 r2 r4 | }
}

\new StaffGroup <<
  \new Staff \with { instrumentName = "Score" } \keepWithTag #'score \ebass
  \new Staff \with { instrumentName = "Part" } \keepWithTag #'part \ebass
>>
and I get the attached output, which is exactly what I want. And it
makes my input files so much easier to read and manage.

Thanks ever so much for your help!

Kind regards,
sb

-- 
Do not meddle in the affairs of trombonists, for they are subtle and
quick to anger.

2022-06-01 17_16_44-Untitled (2) [modified] – Frescobaldi.png
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