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rose-ash/lib/minikanren/run.sx
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mk: phase 3 — run* / run / reify, 18 new tests
run.sx: reify-name builds canonical "_.N" symbols; reify-s walks a term
left-to-right and assigns each unbound var its index in the discovery
order; reify combines the two with two walk* passes. run-n is the
runtime defmacro: binds the query var, takes ≤ n stream answers, reifies
each. run* and run are sugar around it.

First classic miniKanren tests green:
  (run* q (== q 1))                              → (1)
  (run* q (conde ((== q 1)) ((== q 2))))         → (1 2)
  (run* q (fresh (x y) (== q (list x y))))       → ((_.0 _.1))

128/128 cumulative.
2026-05-07 20:03:42 +00:00

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;; lib/minikanren/run.sx — Phase 3: drive a goal + reify the query var.
;;
;; reify-name N — make the canonical "_.N" reified symbol.
;; reify-s term rs — walk term in rs, add a mapping from each fresh
;; unbound var to its _.N name (left-to-right order).
;; reify q s — walk* q in s, build reify-s, walk* again to
;; substitute reified names in.
;; run-n n q-name g... — defmacro: bind q-name to a fresh var, conj goals,
;; take ≤ n answers from the stream, reify each
;; through q-name. n = -1 takes all (used by run*).
;; run* — defmacro: (run* q g...) ≡ (run-n -1 q g...)
;; run — defmacro: (run n q g...) ≡ (run-n n q g...)
;; The two-segment form is the standard TRS API.
(define reify-name (fn (n) (make-symbol (str "_." n))))
(define
reify-s
(fn
(term rs)
(let
((w (mk-walk term rs)))
(cond
((is-var? w) (extend (var-name w) (reify-name (len rs)) rs))
((mk-list-pair? w) (reduce (fn (acc a) (reify-s a acc)) rs w))
(:else rs)))))
(define
reify
(fn
(term s)
(let
((w (mk-walk* term s)))
(let ((rs (reify-s w (empty-subst)))) (mk-walk* w rs)))))
(defmacro
run-n
(n q-name &rest goals)
(quasiquote
(let
(((unquote q-name) (make-var)))
(map
(fn (s) (reify (unquote q-name) s))
(stream-take
(unquote n)
((mk-conj (splice-unquote goals)) empty-s))))))
(defmacro
run*
(q-name &rest goals)
(quasiquote (run-n -1 (unquote q-name) (splice-unquote goals))))
(defmacro
run
(n q-name &rest goals)
(quasiquote (run-n (unquote n) (unquote q-name) (splice-unquote goals))))