zip

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 MutableMap where each value is a Pair that combines the value of the current MutableMap and the provided Traversable

public function zip<Tu>(
  Traversable<Tu> $traversable,
): MutableMap<Tk, Pair<Tv, Tu>>;

If the number of values of the current MutableMap are not equal to the number of elements in the Traversable, then only the combined elements up to and including the final element of the one with the least number of elements is included.

The keys associated with the current MutableMap remain unchanged in the returned MutableMap.

Parameters

• Traversable<Tu>$traversable - The Traversable to use to combine with the elements of the current MutableMap.

Returns

• MutableMap<Tk,Pair<Tv, Tu>> - The MutableMap that combines the values of the current MutableMap with the provided Traversable.