FRP in Lean: Composing invariant-transforming combinators

Sorry that it’s been awhile since my last post! Big life stuff happening over here! Last time we designed a mechanism to accumulate stateful computation on Signals and Events. This design ended up looking a lot like a tiny version of the step-based reactive systems we designed in part 1, so some of you may have been wondering what the point of doing that is. We’ll answer that today: in this post…