FRP in Lean: Reactive Events and LTL.eventually

Last time, we introduced Signals, which are time-varying datatypes: at all time steps t , a Signal a produces some value of type a . We also saw that because an a is always available, the type of a Signal a is LTL.always a . So, we can write □ a to refer both to a a -producing Signal, as well as the universally-quantified temporal proposition. An Event occurs at some point in time The dual of a…