You method does not remove the total number of elements in the array which can potentially cause problems in the future:

...
#assume @ar is filled with this stuff
__END__
/tmp
/var
/etc
/nonexistent
/home
/nonexistent
[download]

  DB<5> p Dumper \@ar
$VAR1 = [
          '/tmp',
          '/var',
          '/etc',
          '',
          '/home',
          ''
        ];
[download]