core.logic question

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ru

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Sep 11, 2021, 1:15:50 PM9/11/21

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Dear clojure users and team!

I have a simple core.logic program:

(require '[clojure.core.logic :as l]

'[clojure.core.logic.pldb :as db])

(db/db-rel In-zone t z)

(def bd (db/db-fact bd In-zone 'A 'B))

(println

(db/with-db bd

(l/run* [q]

(l/fresh [x y]

(In-zone x y)

(== q 'IN-ZONE)))))

Why I get this error message?

user=> (load-file "../programs/corelogic/search2.clj")

CompilerException java.lang.ClassCastException: class clojure.core.logic.LVar cannot be cast to class java.lang.Number (clojure.core.logic.LVar is in unnamed module of loader clojure.lang.DynamicClassLoader @233ae292; java.lang.Number is in module java.base of loader 'bootstrap'), compiling:(/home/ru/clojure/core.logic/../programs/corelogic/search2.clj:8:1)

No any mention about numbers!

Thanks in advance for the help.

Sincerely,

ru

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Sep 30, 2021, 2:49:52 AM9/30/21

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Thanks to Tom: Mistake in "(== q 'IN-ZONE)". Must be "(l/== q 'IN-ZONE)"

By the way. Can anybody recommend comprehensive documentation on core.logic and its API, with examples and so on? All I have found is sketchy and fragmentary..