((type= type (specifier-type 'float)) 'float)
((type= type (specifier-type 'real)) 'real)
((type= type (specifier-type 'sequence)) 'sequence)
- ((type= type (specifier-type 'string-stream)) 'string-stream)
(t `(or ,@(mapcar #'type-specifier (union-type-types type))))))
;;; Two union types are equal if they are each subtypes of each