Is it possible to stop parsing once you find what you are looking for in a big XML file? My code looks like this:

use XML::SAX::ExpatXS;
use WDSTreeHandler;
...
my $tree = read_file("/x/y/z/aap.xml");
my $handler = WDSTreeHandler->new;
my $parser = XML::SAX::ExpatXS->new(Handler => $handler);
$parser->parse_string($tree);
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With the WDSTreeHandler looking like so:

package WDSTreeHandler;
use base qw(XML::SAX::Base);
...
sub start_document
{
    my ($self, $doc) = @_;
}

sub start_element
{
    my ($self, $el) = @_;
    ...
    if ($level >= 0 && $el->{'LocalName'} =~ /folder|leaf/)
    {
        ## do some stuff and try to STOP PARSING
    }
}
sub end_element
{
    ...
}
sub end_document
{
}
1;
[download]

How do you stop parsing?