extractByKey() public method

Extract by key
public extractByKey ( Traversable $iterator, string $key ) : mixed
$iterator Traversable
$key string
return mixed NULL or whatever we found at $key
 /**
  * @test
  * @dataProvider simpleStructures
  */
 public function extractByKeyExtractsKeyByPath($structure, $key, $expected)
 {
     $this->assertSame($expected, $this->fixture->extractByKey($structure, $key));
 }