in reply to Splitting IP ranges depending on overlap conditions

I don't know of any modules that do exactly as you want with IP addresses. But it is useful to note that IPv4 addresses can be packed into a 32 bit integer, so ranges of IP adresses can be mapped into ranges of integers. Then you may use a module called Set::IntSpan to manipulate ranges to your hearts content:
use Set::IntSpan qw(grep_set map_set); $Set::IntSpan::Empty_String = $string; $set = new Set::IntSpan $set_spec; $valid = valid Set::IntSpan $run_list; $set = copy $set $set_spec; $run_list = run_list $set; @elements = elements $set; @spans = spans $set; $u_set = union $set $set_spec; $i_set = intersect $set $set_spec; $x_set = xor $set $set_spec; $d_set = diff $set $set_spec; $c_set = complement $set; # and many more methods
Also there are the modules Array::IntSpan and Array::IntSpan::IP which also manipulate ranges in an array context, but don't seem quite as flexible as Set::IntSpan.

-Mark