EncodingUnion:
    | EncodingClass<"NaN">
    | EncodingClass<"undefined">
    | EncodingClass<"Infinity">
    | EncodingClass<"-Infinity">
    | EncodingClass<"bigint"> & {
        digits: string;
    }
    | EncodingClass<"@@asyncIterator">
    | EncodingClass<"symbol"> & {
        name: string;
    }
    | EncodingClass<"error"> & {
        cause?: Encoding;
        errorId?: string;
        errors?: Encoding[];
        message: string;
        name: string;
    }
    | EncodingClass<"slot"> & {
        iface?: string;
        index: number;
    }
    | EncodingClass<"hilbert"> & {
        original: Encoding;
        rest?: Encoding;
    }
    | EncodingClass<"tagged"> & {
        payload: Encoding;
        tag: string;
    }

Note that the '@@asyncIterator' encoding is deprecated. Use 'symbol' instead.

The 'hilbert' encoding is a reference to the Hilbert Hotel of https://www.ias.edu/ideas/2016/pires-hilbert-hotel . It represents data that has its own '@qclass' property by separately storing the original value of that property and a rest record containing all other properties.