** functions [N]SUBST*, LAST, NRECONC, [N]SUBLIS may return any
object.
** DISASSEMBLE works with closures and funcallable instances.
+ ** ADD-METHOD now returns the generic function, not the new
+ method.
+ ** FIND-METHOD signals an error if the lengths of the specializers
+ is incompatible with the generic function, even if the ERRORP
+ argument is true.
planned incompatible changes in 0.8.x:
* (not done yet, but planned:) When the profiling interface settles