use strictures;
use XML::Smart;
use Aspect;

open my $fh, "<", "xml.xml" or die $!;

my $logString = do { local $/; <$fh> };

around {
    my $return = $_->original->($_->args);
    $_->return_value( $return == 4 ? 2 : $return );
} call "XML::Smart::_data_type";

my $test = XML::Smart->new($logString);

print $test->data;