I'd like to have some clarification on the following claims:

  - Rust async is a mess
  - Python async is a mess

What does "mess" means here?

I have been writing Rust code for a few months, and Python code for more than a decade. I have to admit that I do not know the internals of the Python's async model, but as a "user", I think that trio (and asyncio with 3.10 / 3.11 is getting better) is really great.

The ability to call `trio.run` / `asyncio.run` anywhere to start an async loop does not "contaminate" the async/await keywords up to the entrypoint. Which is great.

In Python, calling an async function returns a coroutine object (that can be awaited). In Javascript it returns a Promise. In Rust it returns a Future.

From the "user" point of view, it's all the same. And I don't know many developers who are interested in how it works under the hood, because (like in math/physics/science in general) it's very useful to sit on the shoulders of others.

If I understand correctly, Rust gives you the tools, and the "shoulders" belong to the library developers (like tokio). Which is fine to me.

So, I really do not understand what "mess" means, what it refers to, and what I (as a "user") can do about it. Also, if the internals change, how will this impact my code?