Hey @djspiewak, first of all: Really cool to see, that you pick up PWD again! I just wanted to ask whether you have seen our PWD based Scala implementation: https://github.com/b-studios/fcd It is the implementation accompanying our parsing with first class derivatives paper (OOPSLA16). We implemented many of the compaction rules by double dispatch and overriding in the corresponding parser implementations.
@b-studios I haven't seen your implementation! I'll take a look. I'm particularly interested in the performance you're able to get. Thus far, parseback has proven to be enormously slow.