Re: Inputting music in parts

[Jean Abou Samra]

Le 06/01/2022 à 21:36, Paulo Matos a écrit :
> Hi,
>
> I have some music I want to transcribe that has 2 parts: A and B the
> music goes:
> part A
> part B
> part A with special ending
>
> I could of course define variables like:
> \partA =
> \partAtransition =
> \partAending =
> \partB =
>
> and then write the music as
> \partA
> \partAtransition
> \partB
> \partA
> \partAending
>
> However, I would like to simplify the final score. What's the best way
> to write this? I saw repeats but that doesn't seem to be exactly what I
> need.
>
> However the partA with different endings sound like it could be where I
> could use \alternative, but unsure how to put it all together. Any
> suggestions?


You can use \unfoldRepeats for this purpose. It
takes repeats notated with repeat bars and volta
brackets (or, in very recent and unreleased versions,
segno repeats), and just unfolds them to make them
written out.

\version "2.22.1"

\unfoldRepeats {
  \repeat unfold 2 {
    c'1 %% Part A
  }
  \alternative {
    { d'1 } %% Part A transition and part B
    { e'1 } %% Part A Ending
  }
}


This command is primarily meant for MIDI output,
so it is documented here:
https://lilypond.org/doc/v2.23/Documentation/notation/using-repeats-with-midi

If you need a more complex structure, you might
want the \volta command introduced in version
2.23. It is more flexible than the traditional
way to write \alternative blocks, allowing to
write, e.g.

\alternative {
  \volta 1,2 { ... }
  \volta 3 { ... }
}

See 
https://lilypond.org/doc/v2.23/Documentation/notation/long-repeats.html#alternative-endings

Best,
Jean