Sorry for another beginner question. I just did `v...

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[adam-mcneilly]

Sorry for another beginner question. I just did var hash = if (address != null) address!!.hashCode() else 0 but I'm not entirely sure why smart cast won't work here. I just checked that address isn't null, why do I have to unwrap it? Am I doing this wrong, or is this just how I have to do it?