public static string?GetDataContextPathFragment(this DotvvmBindableObject currentControl) => (string?)currentControl.GetValue(Internal.PathFragmentProperty, inherit: false) ?? (currentControl.GetBinding(DotvvmBindableObject.DataContextProperty, inherit: false) is IValueBinding binding ?
public IBinding GetBinding(string key) => control.GetBinding(group.GetDotvvmProperty(key));