Fun with Finite State Transducers (blog.yossarian.net)

I'm not quite sure I understand how they are applicable, since access patterns itself can be arbitrary complex

For example how is github.event.pull_request.labels[another_variable].name handled?

I've been thinking that FST could be well suited for building routers for web frameworks. I.e. matching request path `/foo/42` to a set of route patterns like `/foo/{id}` etc. As I understand FST should be near perfect for this use and could potentially allow very good performance. Especially if you can construct the FST at compile time. Somewhat surprisingly I haven't seen anyone doing anything in that direction though, and FST literature is bit difficult if you don't have formal NLP background

Actually pushdown transducers are even more fun (context free languages). 13 years ago I played around with visibly push down transducers for format conversion like grammar based binary compression on XML Schema. Can get you down a nice rabbit hole.