public static Process <T2> SelectMany <T1, T2>(this Process <T1> m, Func <T1, Process <T2> > f)
{
return(m.Match(
halt: e => new Halt <T2>(e),
emit: (h, t) => Try(() => f(h)).Concat(() => t.SelectMany(f)),
await: (req, recv) => Await <T2> .Create(req, recv.AndThen(p => p.SelectMany(f))),
cont: cw => new Cont <T2>(cw.Select(p => p.SelectMany(f))),
eval: (effect, next) => new Eval <T2>(effect, next.SelectMany(f))));
}
public static Process <Unit> Delay(int milliseconds)
{
return(Await <Unit> .Create(() =>
{
Thread.Sleep(milliseconds);
return Unit.Only;
},
either => either.Match(
left: ex => new Halt <Unit>(ex),
right: i => new Halt <Unit>(End.Only))));
}
private static Process <T> BufferHelper <TState, T>(TState buffer, Func <TState> @new, Action <T, TState> add,
Func <TState, bool> ready, Func <TState, T> flush)
{
return(Await <T> .Create(() => default(T), either => either.Match(
left: e => new Halt <T>(e),
right: i =>
{
add(i, buffer);
return ready(buffer) ? new Emit <T>(flush(buffer)).Concat(() => BufferHelper(@new(), @new, add, ready, flush)) : new Cont <T>(() => BufferHelper(buffer, @new, add, ready, flush));
})));
}
private static Process <IEither <T1, T2> > HandleBranch <T1, T2>(object l, Func <IEither <Exception, object>, Process <T1> > recvl, Func <IEither <Exception, object>, Process <T2> > recvr, bool isLeft)
{
Process <IEither <T1, T2> > retval;
var pair = (Tuple <object, Func <object> >)l;
if (isLeft)
{
retval = Wye(recvl(pair.Item1.AsRight <Exception, object>()), Await <T2> .Create(pair.Item2, recvr));
}
else
{
retval = Wye(Await <T1> .Create(pair.Item2, recvl), recvr(pair.Item1.AsRight <Exception, object>()));
}
return(retval);
}
public static Process <IEither <T1, T2> > Wye <T1, T2>(Process <T1> p1, Process <T2> p2)
{
var random = new Random();
if (random.Next() % 2 == 0)
{
return(p1.Match(
halt: e => new Halt <IEither <T1, T2> >(e),
emit: (h, t) => new Emit <IEither <T1, T2> >(h.AsLeft <T1, T2>(), Wye(t, p2)),
cont: cw => new Cont <IEither <T1, T2> >(cw.Select(p => Wye(p, p2))),
eval: (effect, next) => new Eval <IEither <T1, T2> >(effect, Wye(next, p2)),
await: (reql, recvl) => p2.Match <Process <IEither <T1, T2> > >(
halt: e => new Halt <IEither <T1, T2> >(e),
emit: (h, t) => new Emit <IEither <T1, T2> >(h.AsRight <T1, T2>(), Wye(Await <T1> .Create(reql, recvl), t)),
cont: cw => new Cont <IEither <T1, T2> >(cw.Select(p => Wye(p1, p))),
eval: (effect, next) => new Eval <IEither <T1, T2> >(effect, Wye(p1, next)),
await: (reqr, recvr) => Await <IEither <T1, T2> > .Create(WhenEither(reql, reqr), x => x.Match(
left: e => new Halt <IEither <T1, T2> >(e),
right: either => either.Match(
left: l => HandleBranch(l, recvl, recvr, true),
right: r => HandleBranch(r, recvl, recvr, false)))))));
}
else
{
return(p2.Match(
halt: e => new Halt <IEither <T1, T2> >(e),
emit: (h, t) => new Emit <IEither <T1, T2> >(h.AsRight <T1, T2>(), Wye(p1, t)),
cont: cw => new Cont <IEither <T1, T2> >(cw.Select(p => Wye(p1, p))),
eval: (effect, next) => new Eval <IEither <T1, T2> >(effect, Wye(p1, next)),
await: (reqr, recvr) => p1.Match <Process <IEither <T1, T2> > >(
halt: e => new Halt <IEither <T1, T2> >(e),
emit: (h, t) => new Emit <IEither <T1, T2> >(h.AsLeft <T1, T2>(), Wye(t, p2)),
cont: cw => new Cont <IEither <T1, T2> >(cw.Select(p => Wye(p, p2))),
eval: (effect, next) => new Eval <IEither <T1, T2> >(effect, Wye(next, p2)),
await: (reql, recvl) => Await <IEither <T1, T2> > .Create(WhenEither(reql, reqr), x => x.Match(
left: e => new Halt <IEither <T1, T2> >(e),
right: either => either.Match(
left: l => HandleBranch(l, recvl, recvr, true),
right: r => HandleBranch(r, recvl, recvr, false)))))));
}
}
public static Process <T> AwaitAndEmit <T>(Func <T> effect)
{
return(Await <T> .Create(effect, result => result.Match <Process <T> >(
left: ex => new Halt <T>(ex),
right: ti => new Emit <T>(ti))));
}
public static Process <T> While <T>(this Process <T> p, Func <bool> predicate)
{
return(Await <T> .Create(predicate, either => either.Match(
left: e => new Halt <T>(e),
right: b => b ? p.Concat(() => p.While(predicate)) : new Halt <T>(End.Only))));
}