Re: Repeat with alternatives

[David Wright]

Quoting address@hidden (address@hidden):

> I’m trying to write a piece that has repeats with alternatives. It seems that 
> “
> \repeat volta 2” is the way to go with supplying the alternatives in “\
> alternative”. However, this seems to work only for alternative endings, while 
> I
> have alternative middle parts.

So what you're wanting is, I take it, to write |:A-B1/B2-C:| and have the
players play A B1 C A B2 C. I suppose the question arises as to where
you draw the line in calling things "repeats". Ssupposing I write
|:A-B1/B2-C-D1/D2-E:| where A, C and E have 1 measure each, and the
rest of the sections each have several...

This also ties into the lyric structure desired in
http://lists.gnu.org/archive/html/lilypond-user/2015-09/msg00592.html
because, for example, your two alternatives might be a way of dealing
with two verses of text where the syllables didn't quite match at that
point.

Having got all that of my chest! the partial solution below is hardly
original. However, unlike Tim's, I haven't refactored the barlines.
This actually makes it look odd to me as the 2nd alternative shouldn't
start with a barline. And unlike Mark's, it doesn't have extra :|
markings that erroneously tell you to go back to the start.

Following David K's contribution, I looked at issue 355 but, without
any version 2.19 to run, I couldn't experiment with the code in
comment #11 (which looks like the final word). It seems to imply that
2.19's alternatives always start a fresh bar, which is not what we
want here where we start on beat 3. And, of course, issue 355 wouldn't
affect Mark's spurious :| markings.

However, my partial solution fails to close the 2nd alternative's
volta bracket, and I don't see any way of doing so. Perhaps someone
more expert could help there with some sort of tweak.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\version "2.18.2"
\score {
  \new Staff {
    \time 4/4
    a'8 b' c' e' c'2
    a'4 b'
    \set Score.repeatCommands = #'((volta #f) (volta "1."))
    d' g'
    \set Score.repeatCommands = #'((volta #f))
    \set Score.repeatCommands = #'((volta #f) (volta "2."))
    \set Timing.measureLength = #(ly:make-moment 2/4)
    d'8 e' f' g'
    \set Score.repeatCommands = #'((volta #f))
    \set Timing.measureLength = #(ly:make-moment 4/4)
    d''4 c'' b' a' % See *
    a'4 b' c'' d'' \bar ":|."
  }
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

* I split the semibreve in order to clarify that the
  barlines are being placed correctly.

Cheers,
David.