But you can tell that it was considered an optimization "bug" not a feature "bug"

I don't know about this instance specifically, but other operators have similarly been changed as a feature (so the result is more in line with expectations), not as an optimization (thought that's obviously a benefit as well).

However, I completely agree that the developers don't want to be held down by any promises in this area. I would consider the exact number of times a variable is accessed to be subject to change.

In reply to Re^4: Undocumented join() feature, now defunct? (expect) by ikegami
in thread Undocumented join() feature, now defunct? by johngg

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