anchor.diff:  
   ;;; Manage tags
   
  +(defun %tests-from-all-tags (&optional (package *package*))
  +  "Return all of the tests that have been tagged."
  +  (loop for tests being each hash-value in (package-tags package)
  +        nconc (copy-list tests) into all-tests
  +        finally (return (delete-duplicates all-tests))))
  +
  +(defun %tests-from-tags (tags &optional (package *package*))
  +  "Return the tests associated with the tags."
  +  (loop with table = (package-tags package)
  +        for tag in tags
  +        as tests = (gethash tag table)
  +        nconc (copy-list tests) into all-tests
  +        finally (return (delete-duplicates all-tests))))
  +
   (defun get-tags (&optional (package *package*))
     "Return a list of the tags in package."
     (let ((tags (package-tags package)))
  
positive.code:            :remove-tests
             :run-tests
             :use-debugger)
    ;; Functions for reporting test results
    (:export :test-names
             :failed-tests
  
negative.code:       (%run-all-thunks package)
        (%run-thunks test-names package)))
  
  (defun run-tags (tags &optional (package *package*))
    "Run the tests associated with the specified tags in package."
    (%run-thunks (get-tagged-tests tags package) package))
  
  ;;; Useful equality predicates for tests
  
  ;;; (LOGICALLY-EQUAL x y) => true or false
  