Should a Knockout computed that reads non-observable state like clock time be a pureComputed?
I'm designing a view model in Knockout 3.x where a computed value derives partly from observables and partly from state that Knockout cannot track, such as the current clock time or a value held in an external store outside the observable graph. My understanding is that ko.pureComputed sleeps whenever it has no subscribers: it stops re-evaluating, ignores ch