HH\ImmSet::filterWithKey

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

Description

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

Since ImmSets 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

  • $callback - The callback containing the condition to apply to the current ImmSet keys and values.

Return Values

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

Examples

See Set::filterWithKey for usage examples.