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mrocklin/goal-ordering-failure.clj

Last active December 11, 2015 01:48
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A simple script to demonstrate the unfortunate importance of goal ordering in `core.logic`.
Raw
goal-ordering-failure.clj
(use `clojure.core.logic)
;; Runs quickly. Prints (1 2,3).
(clojure.pprint/pprint (run* [q] (fresh [x] (== x [1,2,3])
(membero q x))))
;; Hangs
(clojure.pprint/pprint (run* [q] (fresh [x] (membero q x)
(== x [1,2,3]))))
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