/**
* This method evaluates whether the left operand is identical to the right operand.
*
* @access public
* @static
* @param ILinkedList\Type $xs the left operand
* @param Core\Type $ys the right operand
* @return IBool\Type whether the left operand is identical
* to the right operand
*/
public static function id(ILinkedList\Type $xs, Core\Type $ys) : IBool\Type
{
// ===
if ($ys !== null && $xs->__typeOf() == $ys->typeOf()) {
for ($as = $xs, $bs = $ys; !$as->__isEmpty() && !$bs->__isEmpty(); $as = $as->tail(), $bs = $bs->tail()) {
$r = $as->head()->id($bs->head());
if (!$r->unbox()) {
return $r;
}
}
$x_length = $xs->__length();
$y_length = $ys->__length();
if ($x_length == $y_length) {
return IBool\Type::true();
}
}
return IBool\Type::false();
}
