luaL_typename
tname, luaL_typename(L, narg));
lua_pushfstring(L, "%s: %p", luaL_typename(L, idx),
lua_pushstring(L, luaL_typename(L, 1));
luaL_error(L, "invalid replacement value (a %s)", luaL_typename(L, -1));
LUA_QL("concat"), luaL_typename(L, -1), i);