Returns a MutableSet containing the values of the current MutableSet that meet a supplied condition applied to each value

public function filter(
  (function(Tv):bool) $fn,
): MutableSet<Tv>;

Only values that meet a certain criteria are affected by a call to filter(), while all values are affected by a call to map().


  • (function(Tv):bool) $fn - The callback containing the condition to apply to the current MutableSet values.

Return Values