&overload::import( 'overload', # workaround 5.6 reserved keyword warning
    "0+"     => sub { ${$_[0]} },
    "++"     => sub { $_[0] = ${$_[0]} + 1 },
    "--"     => sub { $_[0] = ${$_[0]} - 1 },
    '""'     => sub { ${$_[0]} == 1 ? 'true' : '0' }, # GH 29
    'eq'     => sub {
      my ($obj, $op) = ref ($_[0]) ? ($_[0], $_[1]) : ($_[1], $_[0]);
      if ($op eq 'true' or $op eq 'false') {
        return "$obj" eq 'true' ? 'true' eq $op : 'false' eq $op;
      }
      else {
        return $obj ? 1 == $op : 0 == $op;
      }
    },
    fallback => 1);