addSlow.zig

const warn = std.debug.warn;
const std = @import("std");
const assert = std.debug.assert;
const time = std.time;

var x: i32 = 1;

pub fn main() !void {
    const stdout_file = try std.io.getStdOut();
    try stdout_file.write("Hello, world!\n");
    var frame = addSlow();
    comptime assert(@typeOf(frame) == @Frame(addSlow));

    const ptr: anyframe->void = &frame;
    const any_ptr: anyframe = ptr;

    resume any_ptr;
    await ptr;
    assert(x == 2);
    // If this program encounters pipe failure when printing to stdout, exit
    // with an error.
    warn("TEST! {}\n", x);
    return;
}

fn addSlow() void {
    suspend {
        var ms = toMilliseconds(3);
        var ns = toNanoseconds(ms);
        time.sleep(ns);
        x += 1;
        resume @frame();
    }
}

fn toMilliseconds(seconds: u64) u64 {
    return seconds * 1000;
}

fn toNanoseconds(ms: u64) u64 {
    return ms * 1000000;
}