>>The AS operator is unintuitive but neat... implicit cast returning a null if it fails? Though, this sounds more like a try-catch "see if this works" code, instead of having an IsA(toObj, tcClass) function. What happens if you try to cast a twice subclassed timer as a timer, do you still get a reference to the original object?
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>>>I'd do a bit more type checking in the first one if it was for production - but even as it stands it is safer than the VFP version...
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>>And what's unsafe in it?



>
>(1) You're not checking that toObj is actually an object
>(2) You assume you can access it's BASECLASS' property (the empty object doesn't have that property)

Great point.