use futures::Poll;
use actor::Actor;
use fut::{ActorFuture, IntoActorFuture};
use fut::chain::Chain;
#[derive(Debug)]
#[must_use = "futures do nothing unless polled"]
pub struct Then<A, B, F>
where A: ActorFuture,
B: IntoActorFuture<Actor=A::Actor>
{
state: Chain<A, B::Future, F>,
}
pub fn new<A, B, F>(future: A, f: F) -> Then<A, B, F>
where A: ActorFuture,
B: IntoActorFuture<Actor=A::Actor>,
{
Then {
state: Chain::new(future, f),
}
}
impl<A, B, F> ActorFuture for Then<A, B, F>
where A: ActorFuture,
B: IntoActorFuture<Actor=A::Actor>,
F: FnOnce(Result<A::Item, A::Error>, &mut A::Actor, &mut <A::Actor as Actor>::Context) -> B,
{
type Item = B::Item;
type Error = B::Error;
type Actor = A::Actor;
fn poll(&mut self,
act: &mut A::Actor,
ctx: &mut <A::Actor as Actor>::Context) -> Poll<B::Item, B::Error>
{
self.state.poll(act, ctx, |a, f, act, ctx| {
Ok(Err(f(a, act, ctx).into_future()))
})
}
}