Read the comments from the bottom up. 
my @var =          # Store the elements in @var.
map { $arr[$_] }   # Get the elements at the remaining indexes.
grep { $_ & 1 }    # Filter out the even indexes.
0..$#arr;          # Create a list of @arr's indexes.

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In reply to Re^3: Quicly extracting odd index elements in the array with grep by ikegami
in thread Quicly extracting odd index elements in the array with grep by Anonymous Monk

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