If you are simply incrementing the most minor part of the version you might be able to automate it a bit by capturing that part of the version number and incrementing it in the substitution using the 'e' flag to execute a bit of code.

use strict;
use warnings;

use 5.010;

my $rxSep = qr{[-_.]};

my @versions = qw{
   1.2.3.4
   2.6
   3_4_9
   4-2-13-5
   5
};

foreach my $version ( @versions )
{
    ( my $newVersion = $version ) =~
       s{((?:\d+$rxSep)+)*(\d+)(?!$rxSep)}
       { my $ver = $2; ( defined $1 ? $1 : q{} ) . ++ $ver }e;
    say qq{$version => $newVersion};
}
[download]

The output.

1.2.3.4 => 1.2.3.5
2.6 => 2.7
3_4_9 => 3_4_10
4-2-13-5 => 4-2-13-6
5 => 6
[download]

I hope this is helpful.