Hi David,
I'd love to work it into the codebase. I'm unsure though whether it would be best to leave the TextSpanner engraver in C++ or replace it with a Scheme engraver like this one.
I think we shouldn't have duplicate code between C++ and Scheme. The Text_spanner_engraver is fairly simple, it would be a very reasonable first step to move it to Scheme so that the infrastructure can be built into what you're working on.
Should I do this? Lukas
