I’m excited to see how this turns out. I work with Go every day and I think Io corrects a lot of its mistakes. One thing I am curious about is whether there is any plan for channels in Zig. In Go I often wish IO had been implemented via channels. It’s weird that there’s a select keyword in the language, but you can’t use it on sockets.

Wrapping every IO operation into a channel operation is fairly expensive. You can get an idea of how fast it would work now by just doing it, using a goroutine to feed a series of IO operations to some other goroutine.

It wouldn't be quite as bad as the perennial "I thought Go is fast why is it slow when I spawn a full goroutine and multiple channel operations to add two integers together a hundred million times" question, but it would still be a fairly expensive operation. See also the fact that Go had fairly sensible iteration semantics before the recent iteration support was added by doing a range across a channel... as long as you don't mind running a full channel operation and internal context switch for every single thing being iterated, which in fact quite a lot of us do mind.

(To optimize pure Python, one of the tricks is to ensure that you get the maximum value out of all of the relatively expensive individual operations Python does. For example, it's already handling exceptions on every opcode, so you could win in some cases by using exceptions cleverly to skip running some code selectively. Go channels are similar; they're relatively expensive, on the order of dozens of cycles, so you want to make sure you're getting sufficient value for that. You don't have to go super crazy, they're not like a millisecond per operation or something, but you do want to get value for the cost, by either moving non-trivial amount of work through them or by taking strong advantage of their many-to-many coordination capability. IO often involves moving around small byte slices, even perhaps one byte, and that's not good value for the cost. Moving kilobytes at a time through them is generally pretty decent value but not all IO looks like that and you don't want to write that into the IO spec directly.)

> One thing I am curious about is whether there is any plan for channels in Zig.

The Zig std.Io equivalent of Golang channels is std.Io.Queue[0]. You can do the equivalent of:

    type T interface{}

    fooChan := make(chan T)
    barChan := make(chan T)

    select {
    case foo := <- fooChan:
        // handle foo
    case bar := <- barChan:
        // handle bar
    }

    const T = void;

    var foo_queue: std.Io.Queue(T) = undefined;
    var bar_queue: std.Io.Queue(T) = undefined;

    var get_foo = io.async(Io.Queue(T).getOne, .{ &foo_queue, io });
    defer get_foo.cancel(io) catch {};

    var get_bar = io.async(Io.Queue(T).getOne, .{ &bar_queue, io });
    defer get_bar.cancel(io) catch {};

    switch (try io.select(.{
        .foo = &get_foo,
        .bar = &get_bar,
    })) {
        .foo => |foo| {
            // handle foo
        },
        .bar => |bar| {
            // handle bar
        },
    }

[0] https://ziglang.org/documentation/master/std/#std.Io.Queue.

Have you tried Odin? Its a great language thats also a “better C” but takes more Go inspiration than Zig.

At least Go didn't take the dark path of having async / await keywords. In C# that is a real nightmare and necessary to use sync over async anti-patterns unless willing to re-write everything. I'm glad Zig took this "colorless" approach.

One of the harms Go has done is to make people think its concurrency model is at all special. “Goroutines” are green threads and a “channel” is just a thread-safe queue, which Zig has in its stdlib https://ziglang.org/documentation/master/std/#std.Io.Queue