By the way, for those who aren't familiar with Lenses, it's not a bad thing to think of them as getter/setter pairs (which should be a little unsurprising at th

By the way, for those who aren't familiar with Lenses, it's not a bad thing to think of them as getter/setter pairs (which should be a little unsurprising at this point). They're first class, more principled, and more generalizable than your typical getter/setter pair... but my use of them here is far from unintentional.