Celluloid VS ponyc

Speaking as someone who has used Erlang longer than most, who created a pre-Elixir-like language for Erlang's BEAM VM, and who routinely listens to Carl Hewitt's rants about why Erlang actors are bad, and who tried to make a Ruby actor library after using innumerable other library-level actor solutions...

Celluloid

> Capabilities taken literally are more of a network thing (it's how you prove you have access to a computer that doesn't trust you). On a language, you don't need the capabilities themselves.

You may be thinking of the term in a different context. In this context, they are a general security concept and definitely apply to more than the network, including languages:

https://en.wikipedia.org/wiki/Capability-based_security

http://habitatchronicles.com/2017/05/what-are-capabilities/

https://www.ponylang.io/

etc...

Actors immediately made me think of Pony. https://www.ponylang.io

Or give up and erase all the type information by saying `throws Exception` or `throws Throwable`.

Genericizing throws in particular was tried in Midori [2] and worked out really well (by report). In addition, several less-than-completely-obscure languages are starting to experiment with the algebra of effects in general (as opposed to error handling in particular). Pony (https://www.ponylang.io/), OCaml (https://ocaml.org/manual/5.2/effects.html) and others are experimenting with bringing what Koka (among others; https://koka-lang.github.io/koka/doc/index.html) to the masses.

[1]: https://www.artima.com/articles/the-trouble-with-checked-exc...

For example, the actor's model is not used by a lot of languages, Pony (https://www.ponylang.io/) and Elixir are the only ones that I know, but they address the concurrency problem quite well, while it's a pain to deal with in other languages at large scale.

And that last point is critical. If the language flatly can't represent some concepts it uses, they have to be implemented somewhere else. I had a similar discussion with a proponent for Pony once- the language itself is 100% safe, and fully dependent on C for its runtime and data structures. One of Rust's core strengths is being able to express unsafe concepts, meaning the unsafe code can expose a safe interface that accurately describes its requirements rather than an opaque C ABI. Vale doesn't seem to do that.

"Exterior iteration. Iteration used to be by stack / non-escaping coroutines, which we also called "interior" iteration, as opposed to "exterior" iteration by pointer-like things that live in variables you advance. Such coroutines are now finally supported by LLVM (they weren't at the time) and are actually a fairly old and reliable mechanism for a linking-friendly, not-having-to-inline-tons-of-library-code abstraction for iteration. They're in, like, BLISS and Modula-2 and such. Really normal thing to have, early Rust had them, and they got ripped out for a bunch of reasons that, again, mostly just form "an argument I lost" rather than anything I disagree with today. I wish Rust still had them. Maybe someday it will!"

I remember that one. The change was shortly after I started fooling with Rust and was major. Major as in it broke all the code that I'd written to that point.

"Async/await. I wanted a standard green-thread runtime with growable stacks -- essentially just "coroutines that escape, when you need them too"."

I remember that one, too; it was one of the things that drew me to the language---I was imagining something more like Pony (https://www.ponylang.io/).

"The Rust I Wanted probably had no future, or at least not one anywhere near as good as The Rust We Got."

Almost certainly true. But The Rust We Got is A Better C++, which was never appealing to me because I never liked C++ anyway.

Pony or bust.