diff --git a/lib/cli.ex b/lib/cli.ex
index 872eef8..42e82eb 100644
--- a/lib/cli.ex
+++ b/lib/cli.ex
@@ -12,7 +12,7 @@ defmodule Onigumo.CLI do
       module.main(working_dir)
     else
       :error -> usage_message()
-      {_, _, invalid_switches} when length(invalid_switches) -> usage_message()
+      {_, _, [_ | _]} -> usage_message()
       {_, argv, _} when length(argv) != 1 -> usage_message()
       _ -> usage_message()
     end