hphp/hack/manual/apis/Classes/HH/Pair/toSet.md
:::info[Note] This is a point-in-time snapshot of the API documentation from January 2026. Going forward, we will not be maintaining a public copy of these references, and recommend users to refer to the built-in signature helpers available in the Hack LSP instead for complete and up-to-date information. :::
Returns a Set with the values of the current Pair
public function toSet(): Set<arraykey, mixed>;
Set<arraykey,mixed> - a Set with the current values of the current Pair.This example shows that converting a Pair to a Set also removes duplicate values:
// This Pair contains 'foo' twice
$p = Pair {'foo', 'foo'};
$s = $p->toSet();
\var_dump($s);
This example shows that converting a Pair to a Set will throw a fatal error if the Pair contains a value that's not a string or an int:
$p = Pair {'foo', -1.5};
/* HH_FIXME[4323] Fatal error will be thrown here */
$s = $p->toSet();
\var_dump($s);