Assume that we have the Clojure code below (the syntax is valid, the @foo notation represents the value of foo ). Given this code, which of the following observations is true ?

( def foo ( future
(Thread/sleep 2000) 4000 )
)

(println @ foo)

Question

Assume that we have the Clojure code below (the syntax is valid, the @foo notation represents the value of foo ). Given this code, which of the following observations is  true ? 
 
 ( def  foo ( future     
    (Thread/sleep 2000) 4000 ) 
 )

(println  @ foo)

Answer

The program will generate a run-time error since the value of foo will not be available when the  println  function is invoked

Answer

The  println  invocation will print  4000 , but only after blocking for 2 seconds

Answer

The  println  invocation will print  nil , since the future has not yet completed

Answer

The  println  invocation will print  4000  immediately, and then the thread will sleep for 2 seconds

Answer

The program will deadlock since the main thread will block, and the future will never be able to deliver its output.

Crowdly

Assume that we have the Clojure code below (the syntax is valid, the @foo notati...

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