- int t = scm_to_int (d);
- if (t > 0 && (t & (t-1)) == 0)
- return Duration (intlog2 (t), dots).smobbed_copy ();
- else
- return SCM_UNDEFINED;
+ Duration k;
+
+ if (Duration *dur = unsmob<Duration> (d)) {
+ if (!dots && SCM_UNBNDP (factor))
+ return d;
+ k = *dur;
+ if (dots)
+ k = Duration (k.duration_log (), k.dot_count () + dots)
+ .compressed (k.factor ());
+ } else {
+ int t = scm_to_int (d);
+ if (t > 0 && (t & (t-1)) == 0)
+ k = Duration (intlog2 (t), dots);
+ else
+ return SCM_UNDEFINED;
+ }
+
+ if (!SCM_UNBNDP (factor))
+ k = k.compressed (ly_scm2rational (factor));
+
+ return k.smobbed_copy ();