+template<>
+const cl_LF eval_rational_series<false> (uintC N, const cl_q_series& args, uintC len)
+{
+ if (N==0)
+ return cl_I_to_LF(0,len);
+ var cl_I Q, T;
+ eval_q_series_aux(0,N,args,&Q,&T);
+ return cl_I_to_LF(T,len) / cl_I_to_LF(Q,len);
+}
+
+static void eval_q_series_aux (uintC N1, uintC N2,
+ cl_q_series_stream& args,
+ cl_I* Q, cl_I* T)
+{
+ switch (N2 - N1) {
+ case 0:
+ throw runtime_exception(); break;
+ case 1: {
+ var cl_q_series_term v0 = args.next(); // [N1]
+ *Q = v0.q;
+ *T = 1;
+ break;
+ }
+ case 2: {
+ var cl_q_series_term v0 = args.next(); // [N1]
+ var cl_q_series_term v1 = args.next(); // [N1+1]
+ *Q = v0.q * v1.q;
+ *T = v1.q + 1;
+ break;
+ }
+ case 3: {
+ var cl_q_series_term v0 = args.next(); // [N1]
+ var cl_q_series_term v1 = args.next(); // [N1+1]
+ var cl_q_series_term v2 = args.next(); // [N1+2]
+ var cl_I q12 = v1.q * v2.q;
+ *Q = v0.q * q12;
+ *T = q12 + v2.q + 1;
+ break;
+ }
+ case 4: {
+ var cl_q_series_term v0 = args.next(); // [N1]
+ var cl_q_series_term v1 = args.next(); // [N1+1]
+ var cl_q_series_term v2 = args.next(); // [N1+2]
+ var cl_q_series_term v3 = args.next(); // [N1+3]
+ var cl_I q23 = v2.q * v3.q;
+ var cl_I q123 = v1.q * q23;
+ *Q = v0.q * q123;
+ *T = q123 + q23 + v3.q + 1;
+ break;
+ }
+ default: {
+ var uintC Nm = (N1+N2)/2; // midpoint
+ // Compute left part.
+ var cl_I LQ, LT;
+ eval_q_series_aux(N1,Nm,args,&LQ,<);
+ // Compute right part.
+ var cl_I RQ, RT;
+ eval_q_series_aux(Nm,N2,args,&RQ,&RT);
+ // Put together partial results.
+ *Q = LQ*RQ;
+ // S = LS + 1/LQ * RS, so T = RQ*LT + RT.
+ *T = RQ*LT + RT;
+ break;
+ }
+ }
+}
+
+template<>
+const cl_LF eval_rational_series<false> (uintC N, cl_q_series_stream& args, uintC len)