Splicing with length 0 at offset 0 prepends before the first element.

Splicing with length 0 at offset $#arr inserts before the last element.

Splicing with length 0 at offset @arr inserts after the last element. Splicing at offset > @arr issues a warning:

If OFFSET is past the end of the array, Perl issues a warning, and splices at the end of the array.