function testRecurse()
{
$iter = new \ArrayIterator(['a' => 1, 'b' => 2, 'c' => new \ArrayIterator(['d' => 3, 'e' => 4])]);
$this->assertSame([1, 2, [3, 4]], recurse('iter\\toArray', $iter));
$this->assertSame(['a' => 1, 'b' => 2, 'c' => ['d' => 3, 'e' => 4]], recurse('iter\\toArrayWithKeys', $iter));
}