+ (one-arg-derive-type num
+ (lambda (arg)
+ (flet ((most-negative-bound (l h)
+ (and l h
+ (if (< (type-bound-number l) (- (type-bound-number h)))
+ l
+ (set-bound (- (type-bound-number h)) (consp h)))))
+ (most-positive-bound (l h)
+ (and l h
+ (if (> (type-bound-number h) (- (type-bound-number l)))
+ h
+ (set-bound (- (type-bound-number l)) (consp l))))))
+ (if (numeric-type-real-p arg)
+ (lvar-type num)
+ (let ((low (numeric-type-low arg))
+ (high (numeric-type-high arg)))
+ (let ((new-low (most-negative-bound low high))
+ (new-high (most-positive-bound low high)))
+ (modified-numeric-type arg :low new-low :high new-high))))))
+ #'conjugate))