- (t (or (car (args-type-required type))
- (car (args-type-optional type))
- (args-type-rest type)
- (specifier-type 'null)))))
+ ((car (args-type-required type)))
+ (t (type-union (specifier-type 'null)
+ (or (car (args-type-optional type))
+ (args-type-rest type)
+ (specifier-type 'null))))))