$_->detach for $tree->look_down(static => $args{static} ? 'no' : 'yes');
$_->attr('static', undef) for $tree->look_down(sub {$_[0]->attr('static')});
$_->attr('smap', undef) for $tree->look_down(sub {$_[0]->attr('smap')});
$_->detach for $tree->look_down(static => $args{static} ? 'no' : 'yes');
$_->attr('static', undef) for $tree->look_down(sub {$_[0]->attr('static')});
$_->attr('smap', undef) for $tree->look_down(sub {$_[0]->attr('smap')});