patch 7.4.793
Problem:    Can't specify when not to ring the bell.
Solution:   Add the 'belloff' option. (Christian Brabandt)
diff --git a/src/if_lua.c b/src/if_lua.c
index 571dd62..167e865 100644
--- a/src/if_lua.c
+++ b/src/if_lua.c
@@ -1354,7 +1354,7 @@
     static int
 luaV_beep(lua_State *L UNUSED)
 {
-    vim_beep();
+    vim_beep(BO_LANG);
     return 0;
 }