jolt/.dirge/memory/PITFALLS.md
Yogthos fb66851e06 Phase 4: deftype/defrecord completion
- evaluator.janet: fix set! to handle (.-field obj) shorthand
  Previously only recognized (. obj -field) format
- core.janet: rewrite core-defrecord to emit (deftype ...) instead of
  plain def with array-map constructor
- core.janet: fix core-map? to recognize deftype table instances
  (and returns last truthy, not boolean true — wrap in if)
- core.janet: fix core-count to skip :jolt/deftype key for records
- core.janet: add ->TypeName arrow factory that calls TypeName.
  constructor via Clojure form emission
- 11 new tests: deftype fields/mutation/instance?, defrecord
  construction/map-behavior/fields/factories, record equality
- map->TypeName factory deferred (needs get/symbol resolution fix)
- 317 tests pass, 0 failures
2026-06-02 21:10:33 -04:00

1.2 KiB

Bare tuples in Janet's eval are function calls: (eval [1 2 3]) tries to call 1 as function. Always emit ['tuple 1 2 3] or (tuple 1 2 3) in data-structure emitter. Similarly, (eval (try body (sym handler))) fails because catch is not a Janet special form — must be (try body ([sym] handler)). Discovered during Phase 5/6 compiler work. § Duplicate function definitions in the same file cause hard-to-diagnose "unknown symbol" errors. In compiler.janet, emit-quote-str was defined twice (once before emit-ast dispatch, once before emit-expr section). The second definition compiled but the first was used by emit-ast dispatch — causing "unknown symbol raw-form->janet". Always grep for the fn name before adding a new definition. § Janet break can't be used inside let blocks — break returns from the innermost loop, and in a let, there's no loop. Pattern: use (var found nil) + (while ... (if condition (do (set found val) (break)))) then check found after loop. § core-binding macro: use array-map (plain struct) NOT hash-map/PHM for the binding frame. PHM's phm-get doesn't work with push-thread-bindings' var-get lookup. Symptom: "error: dynamic binding" with no useful message. Fix: emit (array-map [var sym] val ...) instead of (hash-map ...).