use XML::Rules;

my $parser = XML::Rules->new(rules=>{
	widget => 'content by ID',
	language => 'pass no content',
	_default => 'no content'
});

my $data = $parser->parse(\*DATA);

use Data::Dumper;
print Dumper($data);

# $data{english}{1} == "input"

__DATA__
<?xml version="1.0"?>
<language>
    <english>
        <widget ID="1">input</widget>
        <widget ID="2">output</widget>

    </english>
    <deutsch>
        <widget ID="1">eingabe</widget>
        <widget ID="2">ausgabe</widget>
    </deutsch>
</language>