Function checkParentType

packages/forms/src/directives/ng_model.ts:426–432

(parent: ControlContainer | null)

}

function checkParentType(parent: ControlContainer | null) {
  if (!(parent instanceof NgModelGroup) && parent instanceof AbstractFormGroupDirective) {
    throw formGroupNameException();
  } else if (!(parent instanceof NgModelGroup) && !(parent instanceof NgForm)) {
    throw modelParentException();
  }
}