+ Spanner *after_sp = dynamic_cast<Spanner*> (after);
+ SCM cache_symbol = (is_spaceable (before) && is_spaceable (after))
+ ? ly_symbol2scm ("spaceable-fixed-spacing")
+ : ly_symbol2scm ("loose-fixed-spacing");
+ if (pure)
+ {
+ // The result of this function doesn't depend on "end," so we can reduce the
+ // size of the cache by ignoring it.
+ SCM cached = after_sp->get_cached_pure_property (cache_symbol, start, 0);
+ if (scm_is_number (cached))
+ return robust_scm2double (cached, 0.0);
+ }
+