nullFormCtrl: {
    $$renameControl: ((control: any, name: any) => void);
    $$setSubmitted: (() => void);
    $addControl: (() => void);
    $getControls: (() => any);
    $removeControl: (() => void);
    $setDirty: (() => void);
    $setPristine: (() => void);
    $setSubmitted: (() => void);
    $setValidity: ((...any: any[]) => any);
} = ...