azync

azync is a runtime for running asynchronous tasks in zig.

Example:

const std = @import("std");
const azync = @import("azync");
const Runtime = azync.Runtime;

fn main() void {
    const allocator = std.heap.page_allocator;
    const rt = Runtime.init(allocator);
    defer rt.deinit();

    const future1 = rt.spawn(returnNumber, .{allocator});
    const future2 = rt.spawn(returnSlice1, .{allocator});
    const future3 = rt.spawn(returnSlice2, .{"hello", allocator});

    // Make sure that you await an output type that matches the asynchronous executed function!
    const result1 = future1.Await(i32);
    const result2 = future2.Await([]const u8);
    const result3 = future3.Await([]const u8);
    defer allocator.free(result2);
    defer allocator.free(result3);

    std.debug.print("{d}", .{result1});
    std.debug.print("{s}", .{result2});
    std.debug.print("{s}", .{result3});
}

fn returnNumber() i32 {
    return 42;
}

fn returnSlice1(allocator: std.mem.Allocator) ![]const u8 {

    var str = std.ArrayList(u8).init(allocator);
    defer str.deinit();

    _ = try str.appendSlice("hello");
    _ = try str.appendSlice(" world!");

    return try str.toOwnedSlice();
}

fn returnSlice2(s: []const u8, allocator: std.mem.Allocator) ![]const u8 {

    var str = std.ArrayList(u8).init(allocator);
    defer str.deinit();

    _ = try str.appendSlice(s);
    _ = try str.appendSlice(" world!");

    return try str.toOwnedSlice();
}

azync is a work-stealing runtime. That means it will spawn as many threads as logical cores are available on your machine. On each of them it will run a worker function that will iterate over all tasks that you spawn by calling Runtime.spawn and pick the next pending task. Finished tasks will remain in the task queue as long as you call the Await()method on a spawned task (which is represented by a *Future). Await is written with a capital "A" to distinguish it from the await keyword in Zig, which is already reserved. You can also spawn the threads on a chosen number of logical cores by using initWithCores():

const allocator = std.heap.page_allocator;

const rt = Runtime.initWithCores(16, allocator);
defer rt.deinit();