Rational#**

VALUE
rb_rational_pow(VALUE self, VALUE other)
{
    if (k_numeric_p(other) && k_exact_zero_p(other))
        return f_rational_new_bang1(CLASS_OF(self), ONE);

    if (k_rational_p(other)) {
        get_dat1(other);

        if (f_one_p(dat->den))
            other = dat->num; /* c14n */
    }

    /* Deal with special cases of 0**n and 1**n */
    if (k_numeric_p(other) && k_exact_p(other)) {
        get_dat1(self);
        if (f_one_p(dat->den)) {
            if (f_one_p(dat->num)) {
                return f_rational_new_bang1(CLASS_OF(self), ONE);
            }
            else if (f_minus_one_p(dat->num) && RB_INTEGER_TYPE_P(other)) {
                return f_rational_new_bang1(CLASS_OF(self), INT2FIX(rb_int_odd_p(other) ? -1 : 1));
            }
            else if (INT_ZERO_P(dat->num)) {
                if (rb_num_negative_p(other)) {
                    rb_num_zerodiv();
                }
                else {
                    return f_rational_new_bang1(CLASS_OF(self), ZERO);
                }
            }
        }
    }

    /* General case */
    if (FIXNUM_P(other)) {
        {
            VALUE num, den;

            get_dat1(self);

            if (INT_POSITIVE_P(other)) {
                num = rb_int_pow(dat->num, other);
                den = rb_int_pow(dat->den, other);
            }
            else if (INT_NEGATIVE_P(other)) {
                num = rb_int_pow(dat->den, rb_int_uminus(other));
                den = rb_int_pow(dat->num, rb_int_uminus(other));
            }
            else {
                num = ONE;
                den = ONE;
            }
            if (RB_FLOAT_TYPE_P(num)) { /* infinity due to overflow */
                if (RB_FLOAT_TYPE_P(den))
                    return DBL2NUM(nan(""));
                return num;
            }
            if (RB_FLOAT_TYPE_P(den)) { /* infinity due to overflow */
                num = ZERO;
                den = ONE;
            }
            return f_rational_new2(CLASS_OF(self), num, den);
        }
    }
    else if (RB_BIGNUM_TYPE_P(other)) {
        rb_raise(rb_eArgError, "exponent is too large");
    }
    else if (RB_FLOAT_TYPE_P(other) || RB_TYPE_P(other, T_RATIONAL)) {
        return rb_float_pow(nurat_to_f(self), other);
    }
    else {
        return rb_num_coerce_bin(self, other, idPow);
    }
}