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
KeyedIterable
public function lazy(): KeyedIterable<Tk, Tv>;
Normally, memory is allocated for all of the elements of the
KeyedIterable. With a lazy view, memory is allocated for an element only
when needed or used in a calculation like in map() or filter().
Guide
Returns
KeyedIterable<Tk,Tv>- aKeyedIterablerepresenting the lazy view into the currentKeyedIterable.