As a self-taught programmer with no formal education, I figured writing a lexer/parser toolkit would be a good way to bootstrap my CS knowledge (about 20 years ago). I went down the rabbit hole for months on it, really glad I did.

I can totally relate to the authors interest in error correction of LR parsers, it's a fascinating topic that I also was nerd-sniped by at the time: https://github.com/inxar/syntacs/blob/6461578a04d3b0fda5af20...