add io to a struct and let the struct keep track of its own io.
I don't have a problem with IO conceptually (but I do have a problem with Zig ergonomics, allocator included). I do have a problem with claiming you defeated function coloring.
Like, look. You didn't even get rid of await ...
> try a_future.await(io);
To be clear, where many languages require you to write `const x = await foo()` every time you want to call an async function, in Zig that's just `const x = foo()`. This is a key part of the colorless design; you can't be required to acknowledge that a function is async in order to use it. You'll only use `await` if you first use `async` to explicitly say "I want to run this asynchronously with other code here if possible". If you need the result immediately, that's just a function call. Either way, your caller can make its own choice to call you or other functions as `async`, or not to; as can your callees.
Well, no. In zig that's `const x = foo(io)`.
The moment you take or even know about an io, your function is automatically "generic" over the IO interface.
Using stackless coroutines and green threads results in a completely different codegen.
I just noticed this part of the article:
> Stackless Coroutines > > This implementation won’t be available immediately like the previous ones because it depends on reintroducing a special function calling convention and rewriting function bodies into state machines that don’t require an explicit stack to run. > > This execution model is compatible with WASM and other platforms where stack swapping is not available or desireable.
I wonder what will happen if you try to await a future created with a green thread IO using a stackless coroutine IO.
