protected
    proto.copyTo = bnpCopyTo;
    proto.fromInt = bnpFromInt;
    proto.fromString = bnpFromString;
    proto.clamp = bnpClamp;
    proto.dlShiftTo = bnpDLShiftTo;
    proto.drShiftTo = bnpDRShiftTo;
    proto.lShiftTo = bnpLShiftTo;
    proto.rShiftTo = bnpRShiftTo;
    proto.subTo = bnpSubTo;
    proto.multiplyTo = bnpMultiplyTo;
    proto.squareTo = bnpSquareTo;
    proto.divRemTo = bnpDivRemTo;
    proto.invDigit = bnpInvDigit;
    proto.isEven = bnpIsEven;
    proto.exp = bnpExp;

// public
 