Examples of Merging Pathnames (ANSI and GNU Common Lisp Document)

19.2.3.1 Examples of Merging Pathnames

Although the following examples are possible to execute only in implementations which permit :unspecific in the indicated position andwhich permit four-letter type components, they serve to illustrate the basic concept of pathname merging.

 (pathname-type 
   (merge-pathnames (make-pathname :type "LISP")
                    (make-pathname :type "TEXT")))
⇒  "LISP"

 (pathname-type 
   (merge-pathnames (make-pathname :type nil)
                    (make-pathname :type "LISP")))
⇒  "LISP"

 (pathname-type 
   (merge-pathnames (make-pathname :type :unspecific)
                    (make-pathname :type "LISP")))
⇒  :UNSPECIFIC