How does argument passing work in Clojure? -

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i know in java, if pass object method argument, method let argument variable point same object rather making duplicate. how in clojure? example:

(defn print-from-reader [rdr]    (print (.read rdr)))  (...inside code...   (with-open [rdr (reader file)]     (print-from-rader rdr)))

does print-from-reader make copy of rdr in memory when rdr passed in, or it's pointing same rdr that's created with-open binding?

and there way check if 2 clojure instances pointing same memory?

sorry bad terms such "pointing to" , "instances", newbie in clojure , still learning it. :-)

clojure pass-by-value java. think of as, references passed value. isn't stretch clojure work this, scheme , common lisp behave same way.

you can test whether 2 references point same memory identical?:

(identical? x y)

tests if 2 arguments same object


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