Ok, I found my bug. It was a good one--deeply buried in multiple layers upon layers of indirection and potential off-by-one errors (which it was).
Now time to take Mabel for a walk. Will return to tie up some loose ends and start a ton of code cleanup.
Day 9. Well, made it to the end of Chapter 29 and the end of the basic Lox project. Everything seems to be working. By my clock, I've logged about 54 hours of effort. ed (the standard editor) has logged a total of 3.25 seconds of CPU time in this endeavor.
The final chapter 30 is on some optimization things. Rather than focus on that, I've got a number of loose ends and code cleanup things throughout that I can pursue. So, I'm going to work on that for awhile.
This has been so fun.
If you have a fediverse account, you can quote this note from your own instance. Search https://mastodon.social/users/dabeaz/statuses/115820592207784755 on your instance and quote it. (Note that quoting is not supported in Mastodon.)
Reminds me of the recent post by 
@dabeazDavid Beazley who has been using ed(1) for a rather beastly coding project and reports that, despite the quantity of time spent coding,
> ed…has logged a total of 3.25 seconds of CPU time in this endeavor.
https://mastodon.social/@dabeaz/115820592207784755
svelte coding is becoming a lost art. 😞
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