... the in array @output doesn't contain anything but ... the else block is not executing ...

... because, contrary to what you think, the  @output array contains something. Try printing/dumping the contents of the array. Also, what code are you actually running? 

>perl -wMstrict -le
"my @output = ();
 ;;
 if (@output) {
   print qq{true clause: array not empty};
   }
 else {
   print qq{false clause: array empty};
   }
"
false clause: array empty

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In reply to Re^3: Empty string checking in output by AnomalousMonk
in thread Empty string checking in output by Kumar Mantri

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