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> Paul,
>
> I agree that .NULL. can be a strange animal. But I also agree with Jim
> Nelson that Microsoft's view of .NULL. is correct. It's nonetheless
> inconvienent. What we need is a way of converting .NULL. to a value such
> blank or zero when this is appropriate (as in your SUM() example) . SET
> NULLDISPLAY and the NULLDISPLAY property are steps in the right
direction,
> but these only affect the way .NULL. walues are displayed. This doesn't
> help in calculations.
what about NVL() that returns a non-null value
> My original point about .NULL though. referred to the fact that an object
> reference can return a TYPE("oMyObject")="O" and at the same time
> ISNULL(oMyObject) = .T.. This seems inconsistent. If the object exists,
> shouldn't ISNULL(oMyObject)=.F.? If the object doesn't exist shouldn't
> TYPE("oMyObject")="U"?
VFP (re)defines the type of a variable when you assign a value to it
so the type of the varaible is still Object but it doesn't contain any info
(because the object was released ) so it is set to NULL
Arnon
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