Thread by @Aaronontheweb

For all of the #fsharp bits I tweeted, this is the key takeaway. I can point a new developer on my team at this block of code and say "this is the protocol" and in a separate code file we have a concise FSM that processes all of these

Readably concise, immutable, and fully typed

https://twitter.com/Aaronontheweb/status/1425658566833287171

Can't do that in C# without pressing F12 hundreds of times.

Not _quite_ fully typed - don't provide any hints on how the processor might respond. Not sure how I'd do that just yet.

Also, not sure it's necessary to do that here. A higher level type that expresses an input "ProductUpdateCommand" and an output "ProductResponse" is probably the right place to put that.