> I'm trying to tell Lilypond to print the number of the bars on each
> line with `barNumberDirection'. I tried something like this, but no
> number is printed. Am I doing it wrong ?
The Bar_number_engraver is not included by default.
Use the BarNumberingStaffContext or include the
engraver manually at the Staff or Score level.
I'm sure you can find some example file in
lilypond-x.xx/input/test/ that illustrates this
as well as most other features that are available
but not always that well documented.
/Mats