unfold: volta for typesetting, unfold for MIDI generation?

[Johannes Waldmann]

Hi.

What is the recommended way to obtain the following behaviour
from one and the same source code:
repeats typeset as "\repeat volta N"
(so the page is not filled with duplicates)
but MIDI generated as with "\repeat unfold N"
(so the duplicates are heard).

Thanks, Johannes.

(in other words, "MIDI generation is broken for \repeat volta",
and in fact "the abstract syntax for \alternative is broken",
but these seem to be design decisions ...)