>... under runtime when passing an undefined variable. There was recently some off-line discussion of a problem with the VARTYPE function generating an error if the variable being passed was undefined under runtime conditions. Indeed, I did not see any such error in development. In testing this on a machine with VFP 6 SP3 runtime only, VARTYPE is returning U for undefined variables passed to it.

Mark,

I believe the problem is when vartype() is asked to determine the type of a property for a non-existant object. I believe that it was said that it is by design because vartype() was added to be faster than Type() and therefore is doesn't do the checking the same way and it therefore cannot trap the non-existant object.

All fo this is from memory, so it may not be correct.