[MaxBarraclough]

> I also didn't do a good job restricting computation, selecting time complexity as a metric instead of literally anything else - there are far better ways of doing that.

A tricky one, saying something as tidy as no side effects clearly doesn't work; anything we do has to be a side effect, as our hands are tried regarding return values. I don't think it would be practical to come up with perfectly precise rules for what is appropriate, only guidelines. Even never throw an exception seems too strong, as you might want to do range checks. Never block would complicate logging.

> If the syntax sugar isn't your cup of tea but you agree with using methods over fields

Yes, I think that's where I'm going with this. The advantages of avoiding public fields seem clear enough, we just disagree about the merits of properties.