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mtnygard/multimethod_selector.clj

Created August 23, 2018 16:00
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A clojure.spec.gen.alpha generator that picks a multimethod implementation from the known set.
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multimethod_selector.clj
(defn multimethod-selector
"Returns a generator that picks one dispatch value from the known
dispatch values of a multimethod. Defers the lookup of dispatch
values until sampling time, so any defmethods evaluated after the
generator is created may still be selected."
[s]
#(sgen/bind
(sgen/int)
(fn [i]
(let [ms (keys (methods s))]
(sgen/return (nth ms (mod i (count ms))))))))
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