diff --git a/lapi.c b/lapi.c
index 8747e67e..6db29a61 100644
--- a/lapi.c
+++ b/lapi.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lapi.c,v 1.26 1998/07/12 16:16:02 roberto Exp roberto $
+** $Id: lapi.c,v 1.27 1998/08/21 17:43:44 roberto Exp roberto $
 ** Lua API
 ** See Copyright Notice in lua.h
 */
@@ -452,6 +452,12 @@ lua_Function lua_stackedfunction (int level)
 }
 
 
+int lua_nups (lua_Function func) {
+  TObject *o = luaA_Address(func);
+  return (!o || normalized_type(o) != LUA_T_CLOSURE) ? 0 : o->value.cl->nelems;
+}
+
+
 int lua_currentline (lua_Function func)
 {
   TObject *f = Address(func);
diff --git a/luadebug.h b/luadebug.h
index 088d06ad..12e951cd 100644
--- a/luadebug.h
+++ b/luadebug.h
@@ -1,5 +1,5 @@
 /*
-** $Id: luadebug.h,v 1.1 1997/09/16 19:25:59 roberto Exp roberto $
+** $Id: luadebug.h,v 1.2 1998/06/19 16:14:09 roberto Exp roberto $
 ** Debugging API
 ** See Copyright Notice in lua.h
 */
@@ -24,6 +24,7 @@ char *lua_getobjname (lua_Object o, char **name);
 lua_Object lua_getlocal (lua_Function func, int local_number, char **name);
 int lua_setlocal (lua_Function func, int local_number);
 
+int lua_nups (lua_Function func);
 
 extern lua_LHFunction lua_linehook;
 extern lua_CHFunction lua_callhook;