Defining event classes

[Nathan Ho]

Hi list,

What is the most up-to-date way to define my own event classes?

I've looked at frameEngraver as a model but none of the old versions
seem to be working. The most up-to-date one I could find
(https://lists.gnu.org/archive/html/lilypond-user/2013-07/msg00373.html)
gives me numerous "Event class should be a list" errors and the frames
don't show up in the output, while this one
(https://lists.gnu.org/archive/html/lilypond-user/2013-07/msg00554.html)
spits out a few errors and segfaults. I'm using 2.19.17.

Regards,
Nathan