clojure.core.logic/defne

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Type: macro Added: Clojure unknown Examples: 2 Runnable: 0

([& rest])

Define a goal fn. Supports pattern matching. All patterns will be tried. See conde.

Examples

by stewSquared on 2015-10-08 . May have evaluation errors. ▶

(defne match1 [x y] ([:foo :bar]) ([:baz :qux])) (run* [x y] (match1 x y)) ;; => ([:foo :bar] [:baz :qux]) (defne match2 [x y] ([[a b . tail] [b a . tail]])) (run* [r] (match2 '(a b c d) r)) ;; => ((b a c d)) (defne match3 [x y] ([[a . _] [a . _]])) (run* [r] (match3 [3 2 1] [3 4 5])) ;; => (_0)

by freckletonj on 2016-04-08 . May have evaluation errors. ▶

;; adapted from: ;; http://stackoverflow.com/questions/11964055/constraining-two-vectors-to-be-in-the-same-domain-but-not-be-members-of-each-ot (defne not-membero [x l] ([_ []]) ([_ [?y . ?r]] (!= x ?y) (not-membero x ?r))) (run* [q] (not-membero q [:a :b :c])) ;; ((_0 :- (!= (_0 :a)) (!= (_0 :b)) (!= (_0 :c))) (run* [q] (membero q [1 2 3 4 5]) (not-membero q [2 4])) ;; (1 3 5)

See also

• clojure.core.logic/defna
• clojure.core.logic/defnu
• clojure.core.logic/defnc
• clojure.core.logic/fne
• clojure.core.logic/conde

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