Returns a KeyedIterable containing the values of the current KeyedIterable up to but not including the first value that produces false when passed to the specified callback

public function takeWhile(
  (function(Tv): bool) $fn,
): KeyedIterable<Tk, Tv>;

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


  • (function(Tv): bool) $fn - The callback that is used to determine the stopping condition.