anchor.diff:             (with-dir-ptr-for-fd (dir-ptr (get-fd-current-working-directory))
                (shcl/core/posix:do-directory-contents (file dir-ptr)
                  (when (and (not (or (equal file ".") (equal file "..")))
  -                          (scan next file))
  +                          (funcall next file))
                    (if as-directory-p
                        (with-directory-or-nil (file)
                          (let ((rest (recurse-and-prefix file t)))
  
positive.code:       (return-from make-wild-path-component-from-fragments))
  
      (if (find-if-not 'characterp result)
          (create-scanner
           (nconc (list :sequence :start-anchor) (coerce result 'list) (list :end-anchor))
           :multi-line-mode t)
          (coerce result 'simple-string))))
  
  (defun make-wild-path-from-fragments (fragments)
  
negative.code: component doesn't start with a slash, then the path may be assumed to
  be relative.
  
  A wildcard component of the path is simply a funcallable object.  It
  should accept a string representing a file and return non-nil if that
  file would be acceptable.
  
  How wild!"
    file-name
  