HH\Set::keys
Returns a Vector containing the values of the current Set
public function keys(): Vector<arraykey>;
Sets don't have keys, so this will return the values.
This method is interchangeable with toVector() and values().
Returns
Vector<arraykey>- aVector(integer-indexed) containing the values of the currentSet.
Examples
This example shows that keys() returns a Vector of the Set's values because Sets don't have keys:
$s = Set {'red', 'green', 'blue', 'yellow'};
\var_dump($s->keys());