The Hack Set
has a difference
method but I don't see a method called intersect
or any similar one.
How to get an intersection of two sets?
$set1 = Set { 'a', 'x' };
$set2 = Set { 'b', 'c', 'x', 'y' };
$intersection = ??? // Set { 'x' }
I'm not sure why that function doesn't exist, but you can put this code in some utility function:
$intersection = Set {};
foreach ($other as $v) {
if ($set->contains($v)) {
$intersection->add($v);
}
}
Additionally, you can add a check so you iterate the smaller set.
OR, if you like one liners, this also works :)
$set1->filter($x ==> $set2->contains($x))