def _setuie(self, i):
        """Initialise bitstring with unsigned interleaved exponential-Golomb code for integer i.

        Raises CreationError if i < 0.

        """
        if i < 0:
            raise CreationError("Cannot use negative initialiser for unsigned "
                                "interleaved exponential-Golomb.")
        self._setbin_unsafe('1' if i == 0 else '0' + '0'.join(bin(i + 1)[3:]) + '1')