HH\ImmSet::slice

Returns a subset of the current ImmSet starting from a given key up to, but not including, the element at the provided length from the starting key

public function slice(
  int $start,
  int $len,
): ImmSet<Tv>;

$start is 0-based. $len is 1-based. So slice(0,2) would return the elements at key 0 and 1.

The returned ImmSet will always be a proper subset of the current ImmSet.

Parameters

int $start - The starting value in the current ImmSet for the returned ImmSet.
int $len - The length of the returned ImmSet.

ImmSet<Tv> - An ImmSet that is a proper subset of the current ImmSet starting at $start up to but not including the element $start + $len.

See [Set::slice](</hack/reference/class/Set/slice/#examples>) for usage examples.