static function diff($local, $remote, $flags = null)
{
$comp = new coopy_TableComparisonState();
$td = coopy_Coopy::align($local, $remote, $flags, $comp);
$o = coopy_Coopy::getBlankTable($td, $comp);
if ($comp->a !== null) {
$o = $comp->a->create();
}
if ($o === null && $comp->b !== null) {
$o = $comp->b->create();
}
if ($o === null) {
$o = new coopy_SimpleTable(0, 0);
}
$td->hilite($o);
return $o;
}