lazy
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 lazy, access elements only when needed view of the current
Pair
public function lazy(): KeyedIterable<int, mixed>;
Normally, memory is allocated for all of the elements of the Pair.
With a lazy view, memory is allocated for an element only when needed or
used in a calculation like in map() or filter().
That said, Pairs only have two elements. So the performance impact on
a Pair will be not be noticeable in the real world.
Guide
Returns
KeyedIterable<int,mixed>- an integer-keyed KeyedIterable representing the lazy view into the currentPair.