Skip to main content

isEmpty

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.

Checks if the current Set is empty

public function isEmpty(): bool;

Returns​

  • bool - true if the current Set is empty; false otherwise.

Examples​

$s = Set {};
\var_dump($s->isEmpty());

$s = Set {'red', 'green', 'blue', 'yellow'};
\var_dump($s->isEmpty());