Don't fail when generating first id

undone/main.scm

@@ -128,9 +128,11 @@
 
 (define (next-id)
   "Look through all known todo items and get the next id."
+  (if (> (length todo-list) 0)
       (1+ (apply max (map (lambda (elm)
                             (get-field-value id elm 0))
-                      todo-list))))
+                          todo-list)))
+      1))
 
 (define (add args)
   "Add item to the list."