HH\Set::filterWithKey

Returns a Set containing the values of the current Set that meet a supplied condition applied to its "keys" and values.

Description

public function filterWithKey(
  (function(mixed,Tv):bool) $callback,
): Set<Tv>

Returns a Set containing the values of the current Set that meet a supplied condition applied to its "keys" and values.

Since Sets don't have keys, the callback uses the values as the keys as well.

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

Parameters

  • (function(mixed,Tv):bool) $callback - The callback containing the condition to apply to the current Set keys and values.

Return Values

  • Set<Tv> - a Set containing the values after a user-specified condition is applied to the values of the current Set.