David,

>Do you mean that the expression EMPTY(NULL) SHOULD return NULL or DOES return NULL? You said SHOULD, so I guess that is what you mean?

Yes, I mena it SHOULD retunr NULL but EMPTY() does not return NULL as you have said.

>IF NULL
> wait wind "ITs a cold day in hell"
>else
> wait wind 'it is warm in hell'
>endif
>
>IF NOT NULL
> wait wind "ITs a cold day in hell"
>else
> wait wind 'it is warm in hell'
>
>endif

This again is a result of the command IF not handling three valued logicals in which NULL is the third logical value.

So the result is that in VFP we have partial implementation of the NULL value. Some things in VFP do not handle NULL correctly but rather treat it as .F..