I use something like this:
\include "/home/workspace/include/gitDefinitions.ily"
Then in the header declaration, add the \gitCommitish and any other
items desired to the tagline entry:
\header {
title = "Title"
composer = ""
arranger = ""
meter = ""
tagline = \markup { \filename " " \source " " git Version:
\gitCommitish Committed: \gitDateTime
Engraved:
\simple #(strftime "%d - %b - %Y - %H%M " (localtime
(current-time)))
}
}
An example tagline from a score I am editing presently looks like this:
Here \source is just a note to remind me where I got the information i
used. This could be person's name or whatever. For the tagline above,
\source is "null", so that value is missing from the tagline. I hope
that the above is helpful to others.
Regarding your comment about adding an _expression_ to \bookOutputSuffix
-- that is what I am trying to do. That said,
\bookOutputSuffix "\gitCommitish" or \bookOutputSuffix =
\gitCommitish does not work as expected.
string-append and similar functions exist.