 (defconst zk-buffer "*Zk*"
   "Zk buffer name.")
 
+(defconst zk-separator " --- "
+  "Text used to separate file titles and summaries.")
+
+(defconst zk-empty-file-title "[Empty file]"
+  "Text to use as title for empty files.")
+
 ;; Global variables
 
 (defvar zk-mode-hook nil

   (zk-absolute-filename id)))

(defun zk-make-link (id)
  (concat "[[zk:" id "]]"))

(defun zk-lift-id (fname)
  "Extract the zk ID from STR."

  "Initialize hash tables for caching files."
  (setq zk-hash-contents (make-hash-table :test 'equal))
  (setq zk-hash-mtimes (make-hash-table :test 'equal))
  (setq zk-hash-titles (make-hash-table :test 'equal))
  (setq zk-hash-summaries (make-hash-table :test 'equal)))

(defun zk-cache-update-all ()
