public static T Wait <T>(this IEventual <T> eventual, out uint count)
{
count = 0;
while (true)
{
var @event = eventual.Unroll();
switch (@event.Tag)
{
case Event.Now:
var now = (Event <T> .Now)@event;
return(now.Content);
case Event.Later:
var later = (Event <T> .Later)@event;
eventual = later.Content;
count++;
break;
default:
throw new InvalidProgramException("Should never happen.");
}
}
}
public static IEventual <T> Join <T>(this IEventual <IEventual <T> > eventual)
{
return(new Eventual <T>(
unrollF: () =>
{
var @event = eventual.Unroll();
switch (@event.Tag)
{
case Event.Now:
var now = (Event <IEventual <T> > .Now)@event;
return new Event <T> .Later(now.Content);
case Event.Later:
var later = (Event <IEventual <T> > .Later)@event;
return new Event <T> .Later(later.Content.Join());
default:
throw new InvalidProgramException("Should never happen.");
}
}));
}
public static IEventual <B> Fmap <A, B>(this IEventual <A> eventual, Func <A, B> convert)
{
return(new Eventual <B>(
unrollF: () =>
{
var @event = eventual.Unroll();
switch (@event.Tag)
{
case Event.Now:
var now = (Event <A> .Now)@event;
return new Event <B> .Now(convert(now.Content));
case Event.Later:
var later = (Event <A> .Later)@event;
return new Event <B> .Later(later.Content.Fmap <A, B>(convert));
default:
throw new InvalidProgramException("Should never happen.");
}
}));
}
public static T Wait <T>(this IEventual <T> eventual)
{
uint count;
return(eventual.Wait(out count));
}
public Later(IEventual <T> content)
: base(Event.Later)
{
Content = content;
}
public static IEventual <B> Continue <A, B>(this IEventual <A> eventual, Func <A, IEventual <B> > generate)
{
return(eventual.Fmap(generate).Join());
}
