- Moment w = *unsmob_moment (scope_p_->scm_elem ("whole-in-seconds"));
- Moment wholes_per_min = Moment(60) /w;
- int beats_per_min = wholes_per_min / one_beat_mom;
+ SCM wis = ly_symbol2scm ("whole-in-seconds");
+ Moment *w = unsmob_moment (lookup_variable (wis));
+
+ Moment wholes_per_min = Moment (60);
+ if (!w)
+ {
+ programming_error ("wholes-in-seconds not set.");
+ wholes_per_min /= 4;
+ }
+ else
+ {
+ wholes_per_min /= *w;
+ }
+
+ int beats_per_min = int ((wholes_per_min / one_beat_mom).main_part_);