Re: repeats, nested repeats and alternatives

[Mats Bengtsson]

Neil Puttock wrote:
> Hi Yota,
>
> On 9/6/07, *yota moteuchi* <address@hidden 
> <mailto:address@hidden>> wrote:
>
>
>     Here, magically, the second alternative bar vanished... why ?!
>
>
> You can't put overrides (or anything else) between the bracketed 
> sections of \alternative; just put the bar number override inside the 
> second alternative.
Well, you can, but what your code
\alternative {
   { e f e f }
   \set Score.currentBarNumber = #2
   { e f e b}

means is that the first alternative is { e f e f }, your second 
alternative is
\set Score.currentBarNumber = #2 and your third alternative is { e f e b}.
Read section "Music expressions explained" to understand why.

Also, regarding the bar numbering, the typesetting practice varies from 
score to
score. I've seen many scores where the two alternatives are counted as 
separate
measures.

> 3) Collapsing alternatives
>This is more a suggestion than a question but when dealing with big 
orchestral parts, the >\alternative tag is very painful to maintain. 
Indeed, in some case, trumpets have the same >alternatives bars ( i.e. 
alternative 1. and 2. are duplicates) and should/might be collapsed into 
>one bar. While in the conductor it have to remain expanded (because 
flutes have different >altenatives).
>Could this automatic collapsing (and numbering) be implemeted easily 
or obtained via a
>tweak?


One solution is to define your own music function (or rather use two 
alternative
implementations of the same function), which takes two arguments, the 
main part
of the repeat and the alternative. Here's an example. Note that both 
\score blocks
are identical.

\version "2.10.0"
% Definition to use in the individual parts:
repeatSameAlt =
#(define-music-function (parser location repeatbody alternative) 
(ly:music? ly:music?)
#{
 \repeat volta 2 {$repeatbody $alternative }
#})


\score{
 \relative c''{
   \time 3/4
   c c c
   \repeatSameAlt { d d d } { g g g }
 }
}

% Definition to use in the conductors score:
repeatSameAlt =
#(define-music-function (parser location repeatbody alternative) 
(ly:music? ly:music?)
#{
 \repeat volta 2 $repeatbody \alternative{{ $alternative }{ $alternative }}
#})


\score{
 \relative c''{
   \time 3/4
   c c c
   \repeatSameAlt { d d d } { g g g }
 }
}



   /Mats