Why does this anonymous function starting with println result in a NullPointerException?

Posted by noahz on Stack Overflow See other posts from Stack Overflow or by noahz
Published on 2012-09-21T16:18:46Z Indexed on 2012/09/24 3:37 UTC
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I am learning about pmap and wrote the following function:

(pmap #((println "hello from " (-> (Thread/currentThread) .getName)) 
         (+ %1 %2)) 
   [1 1 1] [-1 -1 -1])

When run, the result is a NullPointerException

(hello from  clojure-agent-send-off-pool-4
hello from  clojure-agent-send-off-pool-3
hello from  clojure-agent-send-off-pool-5
NullPointerException   user/eval55/fn--56 (NO_SOURCE_FILE:11)

Why is this happening? I have understood and observed the body of a fn to be an implicit do.

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