> let protocol_from_port = fun port => I think the `fun` keyword isn't fun. The code clearly states `port =>` yet we still have to type `fun` everywhere. Even

> let protocol_from_port = fun port => I think the `fun` keyword isn't fun. The code clearly states `port =>` yet we still have to type `fun` everywhere. Even JavaScript arrow functions (ES6; 2015) don't require this, although admittedly it took 20 years for this to become a popular enough idea.