DataDefinition::offsetExists

public DataDefinition::offsetExists($offset)

public function offsetExists($offset) {
  // PHP's array access does not work correctly with isset(), so we have to
  // bake isset() in here. See https://bugs.php.net/bug.php?id=41727.
  return array_key_exists($offset, $this->definition) && isset($this->definition[$offset]);
}