The whitespace bug described in the original node is the first bug I've had in a while that:

• wasn't caught by syntax checking (it's valid Perl)
• wasn't griped about with strict and warnings on
• wasn't a design error

I've got one of those, though not a whitespace bug. Just recently I was messing with a data-structure that was supposed to be an array of arrays of arrays:

$rect_list = 
  [  [ [0, 0], [3, 9 ] ],
     [ [5, 4], [3, 10] ], 
     [ [7, 8], [9, 11] ]. 
     [ [2, 4], [5, 15] ], 
     [ [1, 9], [9, 13] ], 
   ];
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First question: Can you spot the bug? Second question: Do you know what it does?