(setq range1 (if (listp (cdr range1)) range1 (list range1))
range2 (if (listp (cdr range2)) range2 (list range2))
r1 (car range1)
- r2 (car range2)
+ r2 (car range2)
r1_min (if (consp r1) (car r1) r1)
r1_max (if (consp r1) (cdr r1) r1)
r2_min (if (consp r2) (car r2) r2)