(pcalls & fns)
Executes the no-arg fns in parallel, returning a lazy sequence of their values
user=> (pcalls function-1 function-2 ...)
(result1 result2 ...)
;; pcalls is implemented using Clojure futures. See examples for 'future'
;; for discussion of an undesirable 1-minute wait that can occur before
;; your standalone Clojure program exits if you do not use shutdown-agents.