Defining luaL_newmetatable() for Lua 5.0 code.

src/luasql.c

@@ -80,6 +80,23 @@ void luaL_setfuncs (lua_State *L, const luaL_Reg *l, int nup) {
 }
 #endif
 
+#if !defined(LUA_VERSION_NUM)
+/*
+** Adapted from Lua 5.2.0
+*/
+LUALIB_API int luaL_newmetatable (lua_State *L, const char *tname) {
+	luaL_getmetatable(L, tname);  /* try to get metatable */
+	if (!lua_isnil(L, -1))  /* name already in use? */
+		return 0;  /* leave previous value on top, but return 0 */
+	lua_pop(L, 1);
+	lua_newtable(L);  /* create metatable */
+	lua_pushstring(L, tname);
+	lua_pushvalue(L, -1);
+	lua_settable(L, LUA_REGISTRYINDEX);
+	return 1;
+}
+#endif
+
 /*
 ** Create a metatable and leave it on top of the stack.
 */