in reply to Sorting Outline Numbers

may not be the prettiest w/ the nested maps, but this works for any number of tiers .. it converts the "1.10.4" to "00001.00010.00004" and sorts that, which will sort properly, and then converts back to strip the leading zeros. (Note the caveat that the '%05d' might need to be '%08d' or something.)
use strict; use warnings; my @s = ( "1.0", "1.10", "1.2", "3", "2.0.1", "4.1.1.1", "1.0.1", "1.1 +", "1.0.2", "2.0" ); my @t = map { join ".", map { sprintf '%d', $_ } split(/\./,$_) } sort map { join ".", map { sprintf '%05d', $_ } split(/\./,$_) } @s; print "IN: ", join(" ", @s), "\n"; print "OUT: ", join(" ", @t), "\n"; __END__ IN: 1.0 1.10 1.2 3 2.0.1 4.1.1.1 1.0.1 1.1 1.0.2 2.0 OUT: 1.0 1.0.1 1.0.2 1.1 1.2 1.10 2.0 2.0.1 3 4.1.1.1