Ooo - good point - that's something lcidlc doesn't handle at the moment... If you pass no value into an interim parameter it will get treated as 'empty' rather than not-specified. Should be able to do something here as the engine can distinguish between an expression being in the list, and one that is not.

The 'fetch' methods will fail if there is a type-conversion error so you can't use the result of that to determine whether a default should be used.

Actually, this is easy with a small addition to the externals api - essentially, the 'if (argc > %d)' needs to become - 'if (argc > %d && <check to see if parameter is specified>)'... I'll add this to the branch I'm working on since it needs a new API call (well, addition to an existing one).