From 5c5d2cd1fca2e2e68360e8cdfd51aed06e2e2f19 Mon Sep 17 00:00:00 2001
From: Yogthos <yogthos@gmail.com>
Date: Wed, 17 Jun 2026 14:33:57 -0400
Subject: [PATCH] Chez Phase 1 (increment 3a): persistent collections on the
 Chez RT
MIME-Version: 1.0
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Content-Transfer-Encoding: 8bit

Broaden the Scheme back end past the numeric/functional subset to vectors,
maps, and sets. host/chez/collections.ss adds a copy-on-write persistent
vector and a bitmap HAMT (the structure 0c measured self-hostable) backing
both maps and sets, keyed by jolt-hash and compared by jolt=. emit.janet
emits :vector/:map/:set literals to the rt constructors and lowers the leaf
ops (conj/get/nth/count/assoc/dissoc/contains?/empty?/peek/pop) via the
native-ops path, with a per-op arity gate.

Also: keyword/map literals in fn position lower to jolt-get ((:k m), ({:k v} k));
arity-1 comparisons emit the vacuous jolt truth (Scheme < rejects a non-number
even at arity 1); count returns a flonum and vector indices coerce from flonum,
both consequences of the all-double number model; values.ss = / hash and the
rt printer learn collections (maps/sets render in HAMT order, so the probe
compares unordered values via =, not printed form).

Subset parity 182 -> 433/436 compiled cases (2219/2655 out of subset), 0 new
divergences. The 3 known divergences are dynamic IFn dispatch (a keyword/vector
held in a local, called as a fn) — deferred to the IFn/protocol increment and
allowlisted in the probe. emit-test 31/31, full run-tests green (125 files).
---
 host/chez/collections.ss        | 310 ++++++++++++++++++++++++++++++++
 host/chez/emit.janet            |  63 ++++++-
 host/chez/rt.ss                 |  25 ++-
 host/chez/values.ss             |   3 +
 test/chez/README.md             |  18 +-
 test/chez/emit-test.janet       |  48 +++++
 test/chez/run-corpus-chez.janet |  24 ++-
 7 files changed, 473 insertions(+), 18 deletions(-)
 create mode 100644 host/chez/collections.ss

diff --git a/host/chez/collections.ss b/host/chez/collections.ss
new file mode 100644
index 0000000..14ddfbf
--- /dev/null
+++ b/host/chez/collections.ss
@@ -0,0 +1,310 @@
+;; Phase 1 (jolt-cf1q.2, inc 3a) — persistent collections on the Chez RT.
+;;
+;; The vector / map / set the emitted programs construct from literals and
+;; operate on via the lowered leaf ops (conj/get/nth/count/assoc/...). Loaded by
+;; rt.ss after values.ss; jolt=2 / jolt-hash (values.ss) call into the
+;; jolt-coll? / jolt-coll=? / jolt-coll-hash hooks defined here (forward refs,
+;; resolved at run time — nothing is CALLED during load).
+;;
+;; Phase note: the persistent vector is a copy-on-write Scheme vector and the
+;; map/set are a bitmap HAMT (the structure 0c measured self-hostable). They live
+;; in Scheme for the Phase-1 bootstrap; the 0c decision is to SELF-HOST them in
+;; Clojure once core is up on Chez (Phase 3 shim shrink). Correctness, not perf,
+;; is the Phase-1 gate.
+
+;; ============================================================================
+;; small immutable-vector helpers (manual; avoid stdlib arg-order ambiguity)
+;; ============================================================================
+(define (vec-copy-range v start end)
+  (let ((out (make-vector (fx- end start))))
+    (let loop ((i start))
+      (when (fx<? i end) (vector-set! out (fx- i start) (vector-ref v i)) (loop (fx+ i 1))))
+    out))
+(define (vec-insert v i x)            ; copy of v with x spliced in at index i
+  (let* ((n (vector-length v)) (out (make-vector (fx+ n 1))))
+    (let loop ((j 0)) (when (fx<? j i) (vector-set! out j (vector-ref v j)) (loop (fx+ j 1))))
+    (vector-set! out i x)
+    (let loop ((j i)) (when (fx<? j n) (vector-set! out (fx+ j 1) (vector-ref v j)) (loop (fx+ j 1))))
+    out))
+(define (vec-set v i x)               ; functional update at index i
+  (let ((out (vec-copy-range v 0 (vector-length v)))) (vector-set! out i x) out))
+(define (vec-remove v i)              ; copy of v with index i dropped
+  (let* ((n (vector-length v)) (out (make-vector (fx- n 1))))
+    (let loop ((j 0)) (when (fx<? j i) (vector-set! out j (vector-ref v j)) (loop (fx+ j 1))))
+    (let loop ((j (fx+ i 1))) (when (fx<? j n) (vector-set! out (fx- j 1) (vector-ref v j)) (loop (fx+ j 1))))
+    out))
+
+;; ============================================================================
+;; persistent vector — copy-on-write over a Scheme vector
+;; ============================================================================
+(define-record-type pvec (fields v) (nongenerative chez-pvec-v1))
+(define empty-pvec (make-pvec (vector)))
+(define (jolt-vector . xs) (make-pvec (list->vector xs)))
+(define (pvec-count p) (vector-length (pvec-v p)))
+;; jolt models every number as a double, so vector indices arrive as flonums —
+;; coerce an integer-valued index to a Scheme fixnum before bounds math.
+(define (->idx i) (if (fixnum? i) i (if (flonum? i) (exact (floor i)) i)))
+(define (pvec-nth-d p i d)
+  (let ((v (pvec-v p)) (i (->idx i)))
+    (if (and (fixnum? i) (fx>=? i 0) (fx<? i (vector-length v))) (vector-ref v i) d)))
+(define (pvec-conj p x)
+  (let* ((v (pvec-v p)) (n (vector-length v)) (out (make-vector (fx+ n 1))))
+    (let loop ((i 0)) (when (fx<? i n) (vector-set! out i (vector-ref v i)) (loop (fx+ i 1))))
+    (vector-set! out n x)
+    (make-pvec out)))
+(define (pvec-assoc p i x)            ; i in [0,count]; =count appends
+  (let* ((v (pvec-v p)) (n (vector-length v)) (i (->idx i)))
+    (cond ((and (fx>=? i 0) (fx<? i n)) (make-pvec (vec-set v i x)))
+          ((fx=? i n) (pvec-conj p x))
+          (else (error 'assoc "vector index out of bounds")))))
+(define (pvec-peek p)
+  (let ((n (pvec-count p))) (if (fx=? n 0) jolt-nil (vector-ref (pvec-v p) (fx- n 1)))))
+(define (pvec-pop p)
+  (let ((n (pvec-count p)))
+    (if (fx=? n 0) (error 'pop "can't pop empty vector")
+        (make-pvec (vec-copy-range (pvec-v p) 0 (fx- n 1))))))
+
+;; ============================================================================
+;; bitmap HAMT — keys hashed by jolt-hash, leaves compared by jolt=
+;;   arr slot is one of: leaf (cons k v) | hnode (branch) | hcoll (hash bucket)
+;; ============================================================================
+(define-record-type hnode (fields bm arr) (nongenerative chez-hnode-v1))
+(define-record-type hcoll (fields hash alist) (nongenerative chez-hcoll-v1))
+(define empty-hnode (make-hnode 0 (vector)))
+(define hmask #x3FFFFFFFFFFFFFF)       ; 58-bit non-negative hash window
+(define max-shift 55)
+(define (key-hash k) (fxand (jolt-hash k) hmask))
+(define (chunk h shift) (fxand (fxsra h shift) 31))
+(define (bitpos h shift) (fxsll 1 (chunk h shift)))
+(define (popcount n) (let loop ((n n) (c 0)) (if (fx=? n 0) c (loop (fxand n (fx- n 1)) (fx+ c 1)))))
+(define (arr-index bm bit) (popcount (fxand bm (fx- bit 1))))
+
+;; jolt= alist ops (for hash-collision buckets)
+(define (assoc-jolt k al) (cond ((null? al) #f) ((jolt= (caar al) k) (car al)) (else (assoc-jolt k (cdr al)))))
+(define (alist-replace k v al) (if (jolt= (caar al) k) (cons (cons k v) (cdr al)) (cons (car al) (alist-replace k v (cdr al)))))
+(define (alist-remove k al) (cond ((null? al) '()) ((jolt= (caar al) k) (cdr al)) (else (cons (car al) (alist-remove k (cdr al))))))
+
+;; split two leaves that collided at `shift` into a subtree (or hcoll if the
+;; full hashes are equal / the hash is exhausted).
+(define (split-leaf shift ek ev h k v)
+  (let ((eh (key-hash ek)))
+    (if (or (fx>? shift max-shift) (fx=? eh h))
+        (make-hcoll h (list (cons ek ev) (cons k v)))
+        (let ((ei (chunk eh shift)) (ni (chunk h shift)))
+          (if (fx=? ei ni)
+              (make-hnode (fxsll 1 ei) (vector (split-leaf (fx+ shift 5) ek ev h k v)))
+              (let ((eb (fxsll 1 ei)) (nb (fxsll 1 ni)))
+                (if (fx<? ei ni)
+                    (make-hnode (fxior eb nb) (vector (cons ek ev) (cons k v)))
+                    (make-hnode (fxior eb nb) (vector (cons k v) (cons ek ev))))))))))
+
+(define (node-assoc node shift h k v added)
+  (let* ((bit (bitpos h shift)) (bm (hnode-bm node)) (arr (hnode-arr node)))
+    (if (fx=? 0 (fxand bm bit))
+        (begin (set-box! added #t)
+               (make-hnode (fxior bm bit) (vec-insert arr (arr-index bm bit) (cons k v))))
+        (let* ((i (arr-index bm bit)) (child (vector-ref arr i)))
+          (cond
+            ((hnode? child) (make-hnode bm (vec-set arr i (node-assoc child (fx+ shift 5) h k v added))))
+            ((hcoll? child)
+             (let ((al (hcoll-alist child)))
+               (if (assoc-jolt k al)
+                   (make-hnode bm (vec-set arr i (make-hcoll (hcoll-hash child) (alist-replace k v al))))
+                   (begin (set-box! added #t)
+                          (make-hnode bm (vec-set arr i (make-hcoll (hcoll-hash child) (cons (cons k v) al))))))))
+            ((jolt= (car child) k) (make-hnode bm (vec-set arr i (cons k v))))   ; replace
+            (else (set-box! added #t)
+                  (make-hnode bm (vec-set arr i (split-leaf (fx+ shift 5) (car child) (cdr child) h k v)))))))))
+
+(define (node-get node shift h k default)
+  (let* ((bit (bitpos h shift)) (bm (hnode-bm node)))
+    (if (fx=? 0 (fxand bm bit)) default
+        (let ((child (vector-ref (hnode-arr node) (arr-index bm bit))))
+          (cond ((hnode? child) (node-get child (fx+ shift 5) h k default))
+                ((hcoll? child) (let ((p (assoc-jolt k (hcoll-alist child)))) (if p (cdr p) default)))
+                ((jolt= (car child) k) (cdr child))
+                (else default))))))
+
+(define (node-dissoc node shift h k removed)
+  (let* ((bit (bitpos h shift)) (bm (hnode-bm node)) (arr (hnode-arr node)))
+    (if (fx=? 0 (fxand bm bit)) node
+        (let* ((i (arr-index bm bit)) (child (vector-ref arr i)))
+          (cond
+            ((hnode? child) (make-hnode bm (vec-set arr i (node-dissoc child (fx+ shift 5) h k removed))))
+            ((hcoll? child)
+             (if (assoc-jolt k (hcoll-alist child))
+                 (begin (set-box! removed #t)
+                        (let ((nal (alist-remove k (hcoll-alist child))))
+                          (cond ((null? nal) (make-hnode (fxand bm (fxnot bit)) (vec-remove arr i)))
+                                ((null? (cdr nal)) (make-hnode bm (vec-set arr i (car nal))))   ; collapse to leaf
+                                (else (make-hnode bm (vec-set arr i (make-hcoll (hcoll-hash child) nal)))))))
+                 node))
+            ((jolt= (car child) k)
+             (set-box! removed #t) (make-hnode (fxand bm (fxnot bit)) (vec-remove arr i)))
+            (else node))))))
+
+(define (node-fold node proc acc)     ; (proc k v acc) over every leaf
+  (let ((arr (hnode-arr node)))
+    (let loop ((i 0) (acc acc))
+      (if (fx<? i (vector-length arr))
+          (let ((child (vector-ref arr i)))
+            (loop (fx+ i 1)
+                  (cond ((hnode? child) (node-fold child proc acc))
+                        ((hcoll? child)
+                         (let cl ((al (hcoll-alist child)) (a acc))
+                           (if (null? al) a (cl (cdr al) (proc (caar al) (cdar al) a)))))
+                        (else (proc (car child) (cdr child) acc)))))
+          acc))))
+
+;; ============================================================================
+;; persistent map / set over the HAMT
+;; ============================================================================
+(define-record-type pmap (fields root cnt) (nongenerative chez-pmap-v1))
+(define empty-pmap (make-pmap empty-hnode 0))
+(define pmap-absent (list 'absent))    ; unique missing-key sentinel
+(define (pmap-assoc m k v)
+  (let* ((added (box #f)) (r (node-assoc (pmap-root m) 0 (key-hash k) k v added)))
+    (make-pmap r (if (unbox added) (fx+ (pmap-cnt m) 1) (pmap-cnt m)))))
+(define (pmap-dissoc m k)
+  (let* ((removed (box #f)) (r (node-dissoc (pmap-root m) 0 (key-hash k) k removed)))
+    (make-pmap r (if (unbox removed) (fx- (pmap-cnt m) 1) (pmap-cnt m)))))
+(define (pmap-get m k default) (node-get (pmap-root m) 0 (key-hash k) k default))
+(define (pmap-contains? m k) (not (eq? pmap-absent (node-get (pmap-root m) 0 (key-hash k) k pmap-absent))))
+(define (pmap-fold m proc acc) (node-fold (pmap-root m) proc acc))
+(define (jolt-hash-map . kvs)
+  (let loop ((m empty-pmap) (kvs kvs))
+    (cond ((null? kvs) m)
+          ((null? (cdr kvs)) (error 'hash-map "odd number of map literal entries"))
+          (else (loop (pmap-assoc m (car kvs) (cadr kvs)) (cddr kvs))))))
+
+(define-record-type pset (fields m) (nongenerative chez-pset-v1))
+(define empty-pset (make-pset empty-pmap))
+(define (pset-conj s e) (if (pmap-contains? (pset-m s) e) s (make-pset (pmap-assoc (pset-m s) e e))))
+(define (pset-disj s e) (make-pset (pmap-dissoc (pset-m s) e)))
+(define (pset-contains? s e) (pmap-contains? (pset-m s) e))
+(define (pset-count s) (pmap-cnt (pset-m s)))
+(define (pset-fold s proc acc) (pmap-fold (pset-m s) (lambda (k v a) (proc k a)) acc))
+(define (jolt-hash-set . xs) (let loop ((s empty-pset) (xs xs)) (if (null? xs) s (loop (pset-conj s (car xs)) (cdr xs)))))
+
+;; ============================================================================
+;; leaf ops the emitter lowers core/clojure fns to (mirrors native-ops)
+;; ============================================================================
+(define (jolt-conj1 coll x)
+  (cond ((pvec? coll) (pvec-conj coll x))   ; nil is a valid vector/set element
+        ((pset? coll) (pset-conj coll x))
+        ((pmap? coll)
+         (cond ((jolt-nil? x) coll)                                   ; (conj m nil) = m
+               ((pmap? x) (pmap-fold x (lambda (k v m) (pmap-assoc m k v)) coll))   ; merge
+               ((and (pvec? x) (fx=? 2 (pvec-count x)))
+                (pmap-assoc coll (pvec-nth-d x 0 jolt-nil) (pvec-nth-d x 1 jolt-nil)))
+               (else (error 'conj "conj on a map expects a [k v] pair or a map"))))
+        (else (error 'conj "unsupported collection"))))
+;; (conj nil a b ...) builds a list in Clojure, conj prepending -> (b a). We have
+;; no list type until inc 3b; a reversed pvec is = to that list (sequential =).
+(define (jolt-conj coll . xs)
+  (if (jolt-nil? coll)
+      (make-pvec (list->vector (reverse xs)))
+      (fold-left jolt-conj1 coll xs)))
+
+(define jolt-get
+  (case-lambda
+    ((coll k) (jolt-get coll k jolt-nil))
+    ((coll k d)
+     (cond ((pmap? coll) (pmap-get coll k d))
+           ((pset? coll) (if (pset-contains? coll k) k d))
+           ((pvec? coll) (pvec-nth-d coll k d))
+           ((string? coll) (let ((i (->idx k)))
+                             (if (and (fixnum? i) (fx>=? i 0) (fx<? i (string-length coll))) (string-ref coll i) d)))
+           (else d)))))
+
+(define jolt-nth
+  (case-lambda
+    ((coll i)
+     (let ((i (->idx i)))
+       (cond ((pvec? coll) (let ((v (pvec-v coll)))
+                             (if (and (fx>=? i 0) (fx<? i (vector-length v))) (vector-ref v i)
+                                 (error 'nth "index out of bounds"))))
+             ((string? coll) (string-ref coll i))
+             (else (error 'nth "unsupported collection")))))
+    ((coll i d)
+     (let ((i (->idx i)))
+       (cond ((pvec? coll) (pvec-nth-d coll i d))
+             ((string? coll) (if (and (fx>=? i 0) (fx<? i (string-length coll))) (string-ref coll i) d))
+             (else d))))))
+
+;; jolt models every number as a double, so a count is a flonum — else
+;; (= 2 (count m)) is false (jolt= is exactness-aware: 2.0 vs exact 2).
+(define (jolt-count coll)
+  (exact->inexact
+    (cond ((pvec? coll) (pvec-count coll))
+          ((pmap? coll) (pmap-cnt coll))
+          ((pset? coll) (pset-count coll))
+          ((string? coll) (string-length coll))
+          ((jolt-nil? coll) 0)
+          (else (error 'count "uncountable")))))
+
+(define (jolt-assoc1 coll k v)
+  (cond ((pmap? coll) (pmap-assoc coll k v))
+        ((pvec? coll) (pvec-assoc coll k v))
+        ((jolt-nil? coll) (pmap-assoc empty-pmap k v))
+        (else (error 'assoc "unsupported collection"))))
+(define (jolt-assoc coll . kvs)
+  (let loop ((coll coll) (kvs kvs))
+    (cond ((null? kvs) coll)
+          ((null? (cdr kvs)) (error 'assoc "assoc expects an even number of key/vals"))
+          (else (loop (jolt-assoc1 coll (car kvs) (cadr kvs)) (cddr kvs))))))
+
+(define (jolt-dissoc coll . ks)
+  (cond ((jolt-nil? coll) jolt-nil)
+        ((pmap? coll) (fold-left pmap-dissoc coll ks))
+        (else (error 'dissoc "unsupported collection"))))
+
+(define (jolt-contains? coll k)
+  (cond ((pmap? coll) (pmap-contains? coll k))
+        ((pset? coll) (pset-contains? coll k))
+        ((pvec? coll) (let ((k (->idx k))) (and (fixnum? k) (fx>=? k 0) (fx<? k (pvec-count coll)))))
+        ((jolt-nil? coll) #f)
+        (else #f)))
+
+(define (jolt-empty? coll)
+  (cond ((jolt-nil? coll) #t)
+        ((pvec? coll) (fx=? 0 (pvec-count coll)))
+        ((pmap? coll) (fx=? 0 (pmap-cnt coll)))
+        ((pset? coll) (fx=? 0 (pset-count coll)))
+        ((string? coll) (fx=? 0 (string-length coll)))
+        (else (error 'empty? "unsupported collection"))))
+
+(define (jolt-peek coll)
+  (cond ((pvec? coll) (pvec-peek coll)) ((jolt-nil? coll) jolt-nil) (else (error 'peek "unsupported collection"))))
+(define (jolt-pop coll)
+  (cond ((pvec? coll) (pvec-pop coll)) (else (error 'pop "unsupported collection"))))
+
+;; ============================================================================
+;; equality / hash hooks called from values.ss (jolt=2 / jolt-hash)
+;; ============================================================================
+(define (jolt-coll? x) (or (pvec? x) (pmap? x) (pset? x)))
+(define (jolt-coll=? a b)
+  (cond
+    ((and (pvec? a) (pvec? b))
+     (let ((va (pvec-v a)) (vb (pvec-v b)))
+       (and (fx=? (vector-length va) (vector-length vb))
+            (let loop ((i 0))
+              (or (fx=? i (vector-length va))
+                  (and (jolt= (vector-ref va i) (vector-ref vb i)) (loop (fx+ i 1))))))))
+    ((and (pmap? a) (pmap? b))
+     (and (fx=? (pmap-cnt a) (pmap-cnt b))
+          (pmap-fold a (lambda (k v ok) (and ok (jolt= (pmap-get b k pmap-absent) v))) #t)))
+    ((and (pset? a) (pset? b))
+     (and (fx=? (pset-count a) (pset-count b))
+          (pset-fold a (lambda (e ok) (and ok (pset-contains? b e))) #t)))
+    (else #f)))
+(define (jolt-coll-hash x)
+  (cond
+    ((pvec? x)
+     (let ((v (pvec-v x)))
+       (let loop ((i 0) (h 1))
+         (if (fx=? i (vector-length v)) (bitwise-and h hmask)
+             (loop (fx+ i 1) (bitwise-and (+ (* 31 h) (key-hash (vector-ref v i))) hmask))))))
+    ;; maps/sets hash order-independently (sum), consistent with unordered =
+    ((pmap? x) (bitwise-and (pmap-fold x (lambda (k v a) (+ a (fxxor (key-hash k) (key-hash v)))) 0) hmask))
+    ((pset? x) (bitwise-and (pset-fold x (lambda (e a) (+ a (key-hash e))) 0) hmask))))
diff --git a/host/chez/emit.janet b/host/chez/emit.janet
index 8905762..d00fc6a 100644
--- a/host/chez/emit.janet
+++ b/host/chez/emit.janet
@@ -29,12 +29,22 @@
    "<" "<" ">" ">" "<=" "<=" ">=" ">="
    "=" "jolt=" "inc" "jolt-inc" "dec" "jolt-dec" "not" "jolt-not"
    "min" "min" "max" "max"
-   "mod" "modulo" "rem" "remainder" "quot" "quotient"})
+   "mod" "modulo" "rem" "remainder" "quot" "quotient"
+   # persistent-collection leaf ops (jolt-wgbz) -> rt prims in collections.ss
+   "vector" "jolt-vector" "hash-map" "jolt-hash-map" "hash-set" "jolt-hash-set"
+   "conj" "jolt-conj" "get" "jolt-get" "nth" "jolt-nth" "count" "jolt-count"
+   "assoc" "jolt-assoc" "dissoc" "jolt-dissoc" "contains?" "jolt-contains?"
+   "empty?" "jolt-empty?" "peek" "jolt-peek" "pop" "jolt-pop"})
 
-# Unary ops only legal at arity 1; binary at arity 2. Others (arith/compare) are
-# variadic in both Scheme and jolt, so any arity is fine.
-(def- unary-ops {"inc" true "dec" true "not" true})
-(def- binary-ops {"mod" true "rem" true "quot" true})
+# Per-op arity gate: only lower when the Scheme prim and the jolt fn agree at
+# this arity. Ops absent from the table are variadic (arith/compare/=, the
+# collection constructors, conj/assoc/dissoc) and legal at any arity.
+(def- op-arity
+  {"inc" |(= $ 1) "dec" |(= $ 1) "not" |(= $ 1)
+   "count" |(= $ 1) "empty?" |(= $ 1) "peek" |(= $ 1) "pop" |(= $ 1)
+   "mod" |(= $ 2) "rem" |(= $ 2) "quot" |(= $ 2) "contains?" |(= $ 2)
+   "get" |(or (= $ 2) (= $ 3)) "nth" |(or (= $ 2) (= $ 3))
+   "assoc" |(and (>= $ 3) (odd? $)) "dissoc" |(>= $ 1) "conj" |(>= $ 1)})
 
 # If fnode is a clojure.core (or host) ref to a native-op primitive, return the
 # Scheme op string — only at an arity where the Scheme op and the jolt fn agree.
@@ -44,10 +54,10 @@
             :host (get fnode :name)
             nil))
   (def op (and nm (get native-ops nm)))
+  (def arity-ok (get op-arity nm))
   (cond
     (nil? op) nil
-    (and (get unary-ops nm) (not= nargs 1)) nil
-    (and (get binary-ops nm) (not= nargs 2)) nil
+    (and arity-ok (not (arity-ok nargs))) nil
     op))
 
 (var- recur-target nil)
@@ -74,6 +84,15 @@
                     s
                     (string s ".0")))
     (string? v) (string/format "%j" v)   # quoted+escaped string literal
+    # keyword literal -> (keyword ns name); ns is everything before the first "/"
+    (keyword? v) (let [s (string v) idx (string/find "/" s)]
+                   (if (and idx (> idx 0))
+                     (string "(keyword " (string/format "%j" (string/slice s 0 idx)) " "
+                             (string/format "%j" (string/slice s (inc idx))) ")")
+                     (string "(keyword #f " (string/format "%j" s) ")")))
+    # jolt char value {:ch <codepoint> :jolt/type :jolt/char}
+    (and (struct? v) (= :jolt/char (get v :jolt/type)))
+    (string "(integer->char " (get v :ch) ")")
     (errorf "emit-const: unsupported literal %p" v)))
 
 (defn- emit-binding [b]
@@ -136,16 +155,37 @@
 (defn- stdlib-var? [n]
   (and (= :var (get n :op)) (string/has-prefix? "clojure." (or (get n :ns) ""))))
 
+# jolt's comparison ops are vacuously true at arity 1 and DON'T inspect the arg
+# (so (< :kw) is true), but Scheme's < demands a number even there — special-case.
+(def- cmp1-ops {"<" true ">" true "<=" true ">=" true})
+
+# IFn dispatch for a LITERAL callee (Clojure's "value as fn"): a keyword looks
+# itself up in its arg ((:k m) = (get m :k)); a map/set/vector literal looks up
+# its arg ((m :k) = (get m :k)). The general dynamic case — a local/var holding a
+# keyword — is runtime IFn dispatch, a later increment, and stays out of subset.
+(defn- ifn-kind [fnode]
+  (case (get fnode :op)
+    :const (when (keyword? (get fnode :val)) :keyword)
+    :map :coll :set :coll :vector :coll
+    nil))
+
 (defn- emit-invoke [node]
   (def fnode (nn (get node :fn)))
   (def args (map emit (vv (get node :args))))
   (def nop (native-op fnode (length args)))
+  (def kind (ifn-kind fnode))
+  (def default (if (> (length args) 1) (string " " (in args 1)) ""))
   (cond
     # zero-arg + / * : Scheme's identity is the EXACT 0 / 1, but jolt models every
     # number as a double, so emit the flonum identity to keep (= 0 (+)) true.
     (and nop (empty? args) (= nop "+")) "0.0"
     (and nop (empty? args) (= nop "*")) "1.0"
+    (and nop (= 1 (length args)) (get cmp1-ops nop)) (string "(begin " (first args) " #t)")
     nop (string "(" nop " " (string/join args " ") ")")
+    # (:k coll [default]) -> (jolt-get coll :k [default])
+    (= kind :keyword) (string "(jolt-get " (first args) " " (emit fnode) default ")")
+    # (coll k [default]) -> (jolt-get coll k [default])
+    (= kind :coll) (string "(jolt-get " (emit fnode) " " (first args) default ")")
     (stdlib-var? fnode)
     (errorf "emit: unsupported stdlib fn `%s/%s` (no core on Chez yet)" (get fnode :ns) (get fnode :name))
     (= :host (get fnode :op))
@@ -172,6 +212,15 @@
                    (if (empty? (vv (get node :statements))) "" " ")
                    (emit (get node :ret)) ")")
     :invoke (emit-invoke node)
+    # collection literals -> rt constructors (collections.ss)
+    :vector (string "(jolt-vector " (string/join (map emit (vv (get node :items))) " ") ")")
+    :set    (string "(jolt-hash-set " (string/join (map emit (vv (get node :items))) " ") ")")
+    :map   (let [flat @[]]
+             (each p (vv (get node :pairs))
+               (def p (vv p))
+               (array/push flat (emit (get p 0)))
+               (array/push flat (emit (get p 1))))
+             (string "(jolt-hash-map " (string/join flat " ") ")"))
     :let   (emit-let node)
     :loop  (emit-loop node)
     :recur (emit-recur node)
diff --git a/host/chez/rt.ss b/host/chez/rt.ss
index 24e136b..655a5e2 100644
--- a/host/chez/rt.ss
+++ b/host/chez/rt.ss
@@ -11,6 +11,7 @@
 ;; Emitted programs do `(load "host/chez/rt.ss")`; this loads values.ss in turn.
 
 (load "host/chez/values.ss")
+(load "host/chez/collections.ss")
 
 ;; --- rt arithmetic / logic shims (named in emit.janet's native-ops) ----------
 (define (jolt-inc x) (+ x 1))
@@ -41,7 +42,17 @@
       (number->string (exact x))
       (number->string x)))
 
-;; Minimal pr-str for the program's final value (full printer is Phase 2).
+;; Program-final-value printer. jolt's `-e` prints in str-style: strings raw (no
+;; quotes), chars as `\c`/`\newline`, collections recursively. NOTE: maps/sets
+;; render in HAMT-iteration order, which does NOT match the Janet host's order —
+;; so unordered values are compared via `=` (true/false), not printed form.
+;; The full canonical printer is Phase 2.
+(define (jolt-str-join strs)
+  (cond ((null? strs) "") ((null? (cdr strs)) (car strs))
+        (else (string-append (car strs) " " (jolt-str-join (cdr strs))))))
+(define (jolt-char->string c)
+  (string-append "\\" (case c ((#\newline) "newline") ((#\space) "space") ((#\tab) "tab")
+                        ((#\return) "return") (else (string c)))))
 (define (jolt-pr-str x)
   (cond
     ((jolt-nil? x) "nil")
@@ -49,4 +60,16 @@
     ((eq? x #f) "false")
     ((number? x) (jolt-num->string x))
     ((string? x) x)
+    ((char? x) (jolt-char->string x))
+    ((keyword? x) (let ((ns (keyword-t-ns x)))
+                    (if ns (string-append ":" ns "/" (keyword-t-name x)) (string-append ":" (keyword-t-name x)))))
+    ((jolt-symbol? x) (let ((ns (symbol-t-ns x)))
+                        (if (or (jolt-nil? ns) (not ns) (eq? ns '())) (symbol-t-name x)
+                            (string-append ns "/" (symbol-t-name x)))))
+    ((pvec? x) (let ((acc '())) (let loop ((i (fx- (pvec-count x) 1)))
+                 (when (fx>=? i 0) (set! acc (cons (jolt-pr-str (pvec-nth-d x i jolt-nil)) acc)) (loop (fx- i 1))))
+                 (string-append "[" (jolt-str-join acc) "]")))
+    ((pset? x) (string-append "#{" (jolt-str-join (pset-fold x (lambda (e a) (cons (jolt-pr-str e) a)) '())) "}"))
+    ((pmap? x) (string-append "{" (jolt-str-join
+                 (pmap-fold x (lambda (k v a) (cons (string-append (jolt-pr-str k) " " (jolt-pr-str v)) a)) '())) "}"))
     (else (format "~a" x))))
diff --git a/host/chez/values.ss b/host/chez/values.ss
index 19eb0bf..687d7e2 100644
--- a/host/chez/values.ss
+++ b/host/chez/values.ss
@@ -56,6 +56,8 @@
     ((and (char? a) (char? b)) (char=? a b))
     ((and (string? a) (string? b)) (string=? a b))
     ((and (boolean? a) (boolean? b)) (eq? a b))
+    ;; collections: forward to collections.ss (loaded after this file by rt.ss).
+    ((and (jolt-coll? a) (jolt-coll? b)) (jolt-coll=? a b))
     (else (eq? a b))))
 (define (jolt= a . rest)
   (let loop ((a a) (rest rest))
@@ -78,4 +80,5 @@
     ((string? x) (string-hash x))
     ((char? x) (char->integer x))
     ((boolean? x) (if x 1 2))
+    ((jolt-coll? x) (jolt-coll-hash x))   ; forward to collections.ss
     (else (equal-hash x))))
diff --git a/test/chez/README.md b/test/chez/README.md
index 59f958e..c886462 100644
--- a/test/chez/README.md
+++ b/test/chez/README.md
@@ -48,9 +48,17 @@ compile-time signal) and are counted "out of subset", not as divergences.
 
     JOLT_CHEZ_CORPUS=1 janet test/chez/run-corpus-chez.janet
 
-Baseline (2026-06-17): **182/182 compiled cases pass, 0 divergences**; 2473/2655
-out of subset (await core on Chez). It's a slow report (a Chez subprocess per
-case), so it's gated behind `JOLT_CHEZ_CORPUS` out of the default suite, like the
-benches. `test/chez/emit-test.janet` is the fast Phase-1 unit gate (real
-analyzer → Chez parity for fib/mandelbrot + regressions); both skip cleanly when
+Baseline after inc 3a (persistent collections, jolt-wgbz): **433/436 compiled
+cases pass**, 3 known divergences, 0 NEW; 2219/2655 out of subset (await the seq
+tier + core on Chez). The 3 known divergences are dynamic IFn dispatch — a
+keyword/vector held in a LOCAL and called as a fn (`(let [k :a] (k m))`); the
+STATIC literal forms (`(:a m)`, `({:a 1} :a)`) are supported. They're
+allowlisted in the probe; it exits non-zero on a NEW divergence.
+
+(Prior, inc 2 baseline: 182/182 compiled, 0 divergences, 2473 out of subset.)
+
+It's a slow report (a Chez subprocess per case), so it's gated behind
+`JOLT_CHEZ_CORPUS` out of the default suite, like the benches.
+`test/chez/emit-test.janet` is the fast Phase-1 unit gate (real analyzer → Chez
+parity for fib/mandelbrot + collections + regressions); both skip cleanly when
 `chez` isn't on PATH.
diff --git a/test/chez/emit-test.janet b/test/chez/emit-test.janet
index bc8133b..8e59aa7 100644
--- a/test/chez/emit-test.janet
+++ b/test/chez/emit-test.janet
@@ -25,6 +25,17 @@
 (def oracle-ctx (api/init {:compile? true}))
 (defn oracle [src] (string (api/load-string oracle-ctx src)))
 
+# Canonical CLI oracle (the run-corpus gate's boundary): collection values don't
+# round-trip through (string value) — they need jolt's real `-e` printer. Take
+# the last non-empty stdout line, exactly like run-corpus.janet.
+(defn cli-oracle [src]
+  (def proc (os/spawn ["build/jolt" "-e" src] :p {:out :pipe :err :pipe}))
+  (def out (ev/read (proc :out) 0x100000))
+  (ev/read (proc :err) 0x100000)
+  (os/proc-wait proc)
+  (def lines (filter (fn [l] (not (empty? l))) (string/split "\n" (string/trim (if out (string out) "")))))
+  (if (empty? lines) "" (last lines)))
+
 (def ctx (d/make-ctx))
 
 # 1) constant-folded arithmetic: (+ 1 2) -> the analyzer folds to const 3.
@@ -73,6 +84,43 @@
   (let [[code out err] (d/run-on-chez ctx src)]
     (ok label (and (= code 0) (= out (oracle src))) (string "chez=" out " janet=" (oracle src) " | " err))))
 
+# 3c) persistent collections (jolt-wgbz): vector/map/set literals + leaf ops.
+#   Maps/sets print in jolt's INTERNAL hash order, which a Scheme HAMT won't
+#   reproduce — so unordered cases are checked via `(= ...)` (prints true/false,
+#   exactly how the run-corpus gate compares them), and only ORDERED vectors are
+#   compared by printed form. Parity is still vs the Janet oracle in both shapes.
+(each src [# ordered: direct printed-form parity
+           "[1 2 3]"
+           "(conj [1 2] 3)"
+           "(count [1 2 3])"
+           "(nth [10 20 30] 1)"
+           "(get [10 20 30] 0)"
+           "(peek [1 2 3])"
+           "(pop [1 2 3])"
+           # unordered / boolean: equality-wrapped, order-independent
+           "(= {:a 1 :b 2} {:b 2 :a 1})"
+           "(= {:a 1 :b 2} (assoc {:a 1} :b 2))"
+           "(= 1 (get {:a 1} :a))"
+           "(= 2 (count {:a 1 :b 2}))"
+           "(= 99 (get {:a 1} :z 99))"
+           "(= {:a 1} (dissoc {:a 1 :b 2} :b))"
+           "(= #{1 2 3} (conj #{1 2} 3))"
+           "(= #{1 2} (conj #{1 2} 2))"
+           "(contains? #{1 2} 1)"
+           "(contains? #{1 2} 9)"
+           "(contains? {:a 1} :a)"
+           "(empty? [])"
+           "(empty? [1])"
+           "(empty? {})"
+           "(= [1 2] [1 2])"
+           "(= [1 2] [1 3])"
+           "(= #{1 2} #{2 1})"
+           "(= {1 2} {1 3})"]
+  (let [[code out err] (d/run-on-chez ctx src)
+        want (cli-oracle src)]
+    (ok (string "coll: " src) (and (= code 0) (= out want))
+        (string "chez=" out " janet=" want " | " err))))
+
 # 4) perf signal: emitted fib(30) in-Scheme timing (excludes Chez startup), to
 #    track against the spike ceiling (hand-Scheme fib ~5ms). Informational — the
 #    jolt-truthy? wrapper (~3x) and flonum modeling are known Phase-4 levers.
diff --git a/test/chez/run-corpus-chez.janet b/test/chez/run-corpus-chez.janet
index 28d4317..ff2698e 100644
--- a/test/chez/run-corpus-chez.janet
+++ b/test/chez/run-corpus-chez.janet
@@ -27,9 +27,21 @@
       (seq [i :range [0 (length corpus) stride]] (in corpus i)))
     corpus))
 
+# Known subset divergences: cases that compile but need a feature beyond the
+# current increment. Dynamic IFn dispatch — a keyword/vector held in a LOCAL or
+# var then called as a fn ((let [k :a] (k m))) — is runtime dispatch on the
+# invoke mechanism, deferred to the IFn/protocol increment. The STATIC literal
+# forms ((:a m), ({:a 1} :a)) ARE supported. Allowlisted by label; the gate fails
+# only on a NEW divergence.
+(def known-divergences
+  {"param holding a keyword (IFn leftover)" true
+   "vector-in-local as fn" true
+   "keyword-in-local as fn" true})
+
 (def ctx (d/make-ctx))
 (var compiled 0) (var pass 0) (var out-of-subset 0)
 (def diverged @[])
+(def known-hit @[])
 
 (each row cases
   (def {:expected e :actual a :label l} row)
@@ -44,15 +56,17 @@
         (++ out-of-subset)
         (let [[code out] res]
           (++ compiled)
+          (defn record-div [m] (if (known-divergences l) (array/push known-hit l) (array/push diverged [l m])))
           (cond
-            (not= code 0) (array/push diverged [l (string "exit " code)])
+            (not= code 0) (record-div (string "exit " code))
             (= out "true") (++ pass)
-            (array/push diverged [l (string "got " out)])))))))
+            (record-div (string "got " out))))))))
 
-(printf "\nChez subset parity: %d/%d compiled cases pass  (%d/%d corpus out of subset)"
-        pass compiled out-of-subset (length cases))
+(printf "\nChez subset parity: %d/%d compiled cases pass  (%d/%d out of subset, %d known divergences)"
+        pass compiled out-of-subset (length cases) (length known-hit))
 (when (> (length diverged) 0)
-  (printf "%d divergence(s) within the compiled subset:" (length diverged))
+  (printf "%d NEW divergence(s) within the compiled subset:" (length diverged))
   (each [l m] (slice diverged 0 (min 25 (length diverged)))
     (printf "  [%s] %s" l m)))
 (flush)
+(os/exit (if (> (length diverged) 0) 1 0))