-- Don't inline this until RULE "enumDeltaToInteger" has had a chance to fire
enumDeltaToIntegerFB :: (Integer -> a -> a) -> a
                     -> Integer -> Integer -> Integer -> a
enumDeltaToIntegerFB c n x delta lim
  | delta >= 0 = up_fb c n x delta lim
  | otherwise  = dn_fb c n x delta lim
enumDeltaToIntegerFB :: (Integer -> a -> a) -> a
                     -> Integer -> Integer -> Integer -> a
enumDeltaToIntegerFB c n x delta lim
  | delta >= 0 = up_fb c n x delta lim
  | otherwise  = dn_fb c n x delta lim
enumDeltaToIntegerFB c n x delta lim
  | delta >= 0 = up_fb c n x delta lim
  | otherwise  = dn_fb c n x delta lim