run-func-in-task.vala

#!/usr/bin/env vala --pkg gio-2.0

delegate void Func();

struct Box {
    Func f;
}

async void run (Func f) {
    var dummy = new Object ();
    var task = new Task (dummy, null, () => Idle.add (run.callback));
    Box boxed = { f };
    task.set_task_data ((void*)&boxed, null);
    task.run_in_thread ((task, obj, data, cancel) => {
        Box *b = (Box*) data;
        b.f ();
        task.return_pointer (null, null);
    });
    yield;
}

void main() {
    var loop = new GLib.MainLoop ();
    print ("start\n");
    int i = 3;
    run.begin (() => print (@"running - $i\n"), (obj, res) => {
        run.end (res);
        print ("done\n");
        loop.quit ();
    });
    loop.run ();
    print ("end\n");
}