use strict;
use warnings;
use Data::Dumper;

sub hashify {
    my $path = shift;
    my $h = {};
    my $current = $h;
    for (split '/', $path) {
        next unless length $_;
        $current->{$_} = {};
        $current = $current->{$_};
    }
    return $h;
}

print Dumper hashify('/foo/bar/baz/blubb');

my %x;
while(@ARGV) {
  our $x;
  local $x=\%x;
  ()=shift=~m!/+([^/]+)(?{$x=$x->{$^N}||={}})!g;
}
print Dumper \%x;

/aa///bb/cc/

/dd/dd/ee/ff

$VAR1 = {
          'dd' => {
                    'dd' => {
                              'ee' => {
                                        'ff' => {}
                                      }
                            }
                  },
          'aa' => {
                    'bb' => {
                              'cc' => {}
                            }
                  }
        };