immutable

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 an immutable copy (ImmSet) of the current ImmSet

public function immutable(): ImmSet<Tv>;

This method is interchangeable with toImmSet().

Returns

• ImmSet<Tv> - an ImmSet that is a copy of the current ImmSet.

Examples

See Set::immutable for usage examples.