Comment by messe
Comment by messe 19 hours ago
But you can't call it from synchronous rust. Zig is moving toward all sync code also using the Io interface.
Comment by messe 19 hours ago
But you can't call it from synchronous rust. Zig is moving toward all sync code also using the Io interface.
Let me rephrase, you can't call it like any other function.
In Zig, a function that does IO can be called the same way whether or not it performs async operations or not. And if those async operations don't need concurrency (which Zig expresses separately to asynchronicity), then they'll run equally well on a sync Io runtime.
> In Zig, a function that does IO can be called the same way whether or not it performs async operations or not.
no, you can't, you need to pass a IO parameter
You will need to pass that for synchronous IO as well. All IO in the standard library is moving to the Io interface. Sync and async.
If I want to call a function that does asynchronous IO, I'll use:
foo(io, ...);
foo(io, ...);
io.async(foo, .{ io, ... });
try io.concurrent(foo, .{ io, ... });
Here's a problem with that:
Cannot start a runtime from within a runtime. This happens because a function (like `block_on`) attempted to block the current thread while the thread is being used to drive asynchronous tasks.
Fixed it for you
https://play.rust-lang.org/?version=stable&mode=debug&editio...
But that's the thing, idiomatic Rust sync code almost never passes around handles, even when they need to do I/O.
You might be different, and you might start doing that in your code, but almost none of either std or 3rd party libraries will cooperate with you.
The difference with Zig is not in its capabilities, but rather in how the ecosystem around its stdlib is built.
The equivalent in Rust would be if almost all I/O functions in std would be async; granted that would be far too expensive and disruptive given how async works.
yes, you can:
https://play.rust-lang.org/?version=stable&mode=debug&editio...