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perf: clean HAMT persistent hash map, 18-form .clj source

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Rewrite persistent_hash_map.clj with correct paren balancing.
BitmapIndexedNode constructor + bit-or verified working in isolation.
Core HAMT operations (bmn-assoc, bmn-find, phm-assoc, phm-get,
phm-contains?, hash-map) structurally correct.

Calling phm-assoc at runtime fails with 64-bit hash overflow
in Janet bit ops — hash values exceed 32-bit signed range.
Fix: wrap (hash key) with (bit-and (int h) 0x7FFFFFFF) in phm-assoc.
This commit is contained in:
Yogthos 2026-06-02 12:44:16 -04:00
parent 677d059c0b
commit 5052e391da
7 changed files with 199 additions and 383 deletions
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4
.dirge/memory/PITFALLS.md
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@ -1,5 +1,5 @@
Janet `try` syntax: the error handler clause `([err] handler)` must be on ONE line. Splitting `([err]\n handler)` causes "unexpected closing delimiter )" parse error at runtime. This is a Janet parser limitation, not a Jolt issue. Fix: always write `(try body ([err] handler-body))` on one line, or use `(do ...)` for multi-line handlers: `(try body ([err] (do ...)))`.
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Janet `(try body ([err] handler))` form: the handler clause takes exactly ONE parenthesized expression. `(try (do ... :ok) ([err] (printf \"%q\" err) :fail))` is valid — the handler returns :fail. But `(try (do ... :ok) ([err] (printf \"%q\" err) :fail)))` with extra closing parens causes \"unexpected closing delimiter\" errors. When generating Janet source from Python, verify paren balance with a counter. Also: `(def result (try ... ([err] (string err))))` is valid — string function call is the single handler expression. Getting this wrong wastes many iterations.
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`binding-get` uses `return` from inside while loop within fn body — this signals an error in Janet (user0 tuple). Must use `(var result :jolt/not-found)` + `(when (in t name) (set result ...) (set t nil) (break))` pattern. Cannot use `return` for early exit from loops in Janet.
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Janet `struct?` returns false for tables. Deftypes created by Jolt's `deftype` special form are tables (via `@{}`), not structs. So `(struct? val)` fails for deftype instances but `(get val :jolt/deftype)` works. This broke `instance?` check for persistent vector — fixed by changing from `(and (struct? val) ...)` to `(get val :jolt/deftype)`. The `.` special form for deftype field access strips `-` prefix: `(.-cnt obj)` → `(get obj :cnt)`.