export type Attachment = File;
export declare const Attachment: {
    new (fileBits: BlobPart[], fileName: string, options?: FilePropertyBag): File;
    prototype: File;
};
export type FormDataValue = undefined | null | string | number | boolean | object | Attachment | Attachment[];
export type FormProps = Record<string, FormDataValue>;
export declare const appendAll: (formData: FormData, obj: FormProps) => void;