Well, I found it so ugly the Segno in the staff does not cooperate with the
\repeat volta command.
I installed on my WIN7 offline computer the lilydef VM, got a tarball from
GIT (HTML user interface), and tested my ideas to change it.
In contact with harm6 and Marc Hohl on this toppic, I had a look to the 'end
hook suppression on the volta brackets based on the barline type'. There I
worked to move the 'list of bar lines' from C++ source code to a staff
context property.
Next I had the idea to suppress the 'repeated triggers due to grace notes
during the same main moment' in the engravers for the repeat bar lines (by
\repeat command) and for the volta bracket.
The idea of Marc Hohl was, to make these topic separete pathes, so now I
have exported three git diff extractions to files.
Here a short description of my diffs:
[...]
What shall I do next?
Post the three files (11 KB, 6 KB, 5 KB) here in the mailing list?