$ perl -MDV -e '$x=%x=@x=(2,3); dv(\*x,[1,undef,3])'
0  GLOB(0x80ffe50)
   -> 
         ${*main::x} = 2
         @{*main::x} = (
            0  2
            1  3
         )
         %{*main::x} = (
            2 => 3
         )
1  ARRAY(0x80f5fc4)
   0  1
   1  undef
   2  3