- 02-variables.js: undefined/null/NaN typeof cheat-table; full null
section (independent primitive = 'intentional empty', === null to test,
typeof null bug, placeholder use); cross-ref var pitfall to ch10
- 07-objects.js: add §0 on what an object really is (primitive vs object
camps; arrays/functions are objects — you can attach props)
- flat single-file structure: NN-topic.js per topic (concepts as
comments + demo + exercises in one file), replacing the old
NN-topic/ folder with separate notes.md + practice.js
- 00-concepts/ cross-topic notes (mistakes log, call-forms,
value-vs-reference, shortcircuit bash-vs-js)
- move quokka_playground.js from repo root into js_notes/
- add project CLAUDE.md
Jaydon