Lemmas added. Model same.
Working on a more useful epsilon closure description. Checkpoint.
Invariant is looking good. Got return case done and fixing up the call case. Everything else should be cake.
Difficult cases of invariant proved.
Started with lemmas about map_join. Going to take this offline and go back to paper since the invariant is solid.
minor paper fixes. Switched to sigplan.
Drafted a why-we-matter section.
Small changes. About to remove gratuitous parentheses.
Fixed formatting. Added to metatheory section. Need to prove the correctness theorem for PDCFA and fix the example(s).
Minor intro cleanup.
Merging to push.