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Comment by alethic | Hacker News Reader

... in what regard?

> things have to happen in a certain order. At compile-time, your ordering is checked against certain rules, and certain classes of deadlocks and hangs can be avoided. The order of actions is then enforced at runtime.

This is how imperitive languages work. One line executes before the one below it as a default.

Choreographic languages are often hosted in a functional language like Haskell and OCaml though so the analogy isn’t quite right

I would instead say that choreographic languages enforce global visibility of communication. The global behavior of the system is available syntactically. It doesn’t necessarily or even typically involve mutation, explicit loops, side effects etc at least in the literature.

I appreciate the details! And alethic's explanation in the comments was easy to understand. The key part I missed was that it's a messaging system between software processes. And your insight that it's used in functional programming helps too!

Ah yes, separate software processes is probably the confusion here. Avoiding certain classes of deadlocks and hangs is also something that's not particularly guaranteed by imperative programs. You can throw a type system on it and get some of them (session types I think are quite expressive), but in practice I don't know of any imperative languages with a type system rich enough to do this.

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