@@ -6,21 +6,22 @@

     ((or pathname string) (namestring

                            (truename repo)))))

-(defun ref (repo id)

-  "Given a REPOsitory and a ref ID return the ref-id object."

-  (let ((repo-root (root-of repo)))

-    (or (alexandria:when-let ((object-file (loose-object repo id)))

-          (make-instance 'loose-ref

-                         :repo repo-root

-                         :hash id

-                         :file object-file))

-        (multiple-value-bind (pack offset) (find-object-in-pack-files repo-root id)

-          (when pack

-            (make-instance 'packed-ref

-                           :hash id

+(defgeneric ref (repo id)

+  (:documentation "Given a REPOsitory and a ref ID return the ref-id object.")

+  (:method ((repo git-repository) (id string))

+    (let ((repo-root (root-of repo)))

+      (or (alexandria:when-let ((object-file (loose-object repo id)))

+            (make-instance 'loose-ref

                            :repo repo-root

-                           :offset offset

-                           :pack pack))))))

+                           :hash id

+                           :file object-file))

+          (multiple-value-bind (pack offset) (find-object-in-pack-files repo-root id)

+            (when pack

+              (make-instance 'packed-ref

+                             :hash id

+                             :repo repo-root

+                             :offset offset

+                             :pack pack)))))))

 (defun ensure-ref (thing &optional (repo *git-repository*))

   (typecase thing