Boolean operators (and, or) in Clojure -

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here quote http://www.braveclojure.com/:

clojure uses boolean operators or , and. or returns either first truthy value or last value. and returns first falsey value or, if no values falsey, last truthy value.

why build language? how come across use cases it?

it bit different other languages, handy default values. example:

(defn print-it [x]    (println (or x :unknown)))  > (print-it 5) 5  > (print-it "hi") hi  > (print-it false) :unknown  > (print-it nil) :unknown

so normal value 5 or "hi", result of or expression supplied value. if value nil (or false), default value :unknown returned.


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