The lualang.def file will use a '.' to delimit the start of keywords. This is incorrect since the '.' is a table delimiter and a key in a table is allowed to be the same string as a builtin function. For example, the following would highlight 'error'.
Even though error does not reference the builtin error function. Is there a way to fix this behavoir? It doesn't seem specific to lua but I didn't see anything int the .def that made it obvious how I might go about fixing it.