Number of compilation errors using `select!` macro

[Thomasdezeeuw]

I've tried version "0.3.0-alpha.11" and master at commit 8479bd2.

// Both these values implement `Future` and `FusedFuture`:
let mut timeout = Timer::timeout(&mut ctx, Duration::from_millis(100)).fuse();
let mut msg_future = ctx.receive().fuse();

select! {
    msg = msg_future => println!("Got a message: {}", msg),
    _ = timeout => {
        println!("Getting impatient!");
        return;
    },
};

It causes the following compilation errors.

error[E0433]: failed to resolve: could not find `FusedFuture` in `future`
  --> src/actor/context.rs:87:9
   |
25 | /         select! {
26 | |             msg = msg_future => println!("Got a message: {}", msg),
27 | |             _ = timeout => {
28 | |                 println!("Getting impatient!");
29 | |                 continue;
30 | |             },
31 | |         };
   | |__________^ could not find `FusedFuture` in `future`
   |
   = note: this error originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)

error[E0433]: failed to resolve: could not find `Poll` in `task`
  --> src/actor/context.rs:87:9
   |
25 | /         select! {
26 | |             msg = msg_future => println!("Got a message: {}", msg),
27 | |             _ = timeout => {
28 | |                 println!("Getting impatient!");
29 | |                 continue;
30 | |             },
31 | |         };
   | |__________^ could not find `Poll` in `task`
   |
   = note: this error originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)

error[E0412]: cannot find type `LocalWaker` in module `futures_util::task`
  --> src/actor/context.rs:87:9
   |
25 | /         select! {
26 | |             msg = msg_future => println!("Got a message: {}", msg),
27 | |             _ = timeout => {
28 | |                 println!("Getting impatient!");
29 | |                 continue;
30 | |             },
31 | |         };
   | |__________^ did you mean `LocalWakerRef`?
   |
   = note: this error originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)
help: possible candidates are found in other modules, you can import them into scope
   |
5  | use core::task::LocalWaker;
   |
5  | use futures_core::task::LocalWaker;
   |
5  | use futures_util::core_reexport::task::LocalWaker;
   |
5  | use std::task::LocalWaker;
   |

error[E0412]: cannot find type `Poll` in module `futures_util::task`
  --> src/actor/context.rs:87:9
   |
25 | /         select! {
26 | |             msg = msg_future => println!("Got a message: {}", msg),
27 | |             _ = timeout => {
28 | |                 println!("Getting impatient!");
29 | |                 continue;
30 | |             },
31 | |         };
   | |__________^ not found in `futures_util::task`
   |
   = note: this error originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)
help: possible candidates are found in other modules, you can import them into scope
   |
5  | use core::task::Poll;
   |
5  | use futures_core::Poll;
   |
5  | use futures_core::task::Poll;
   |
5  | use futures_util::core_reexport::task::Poll;
   |
and 1 other candidates

error[E0277]: the size for values of type `[_]` cannot be known at compilation time
  --> src/actor/context.rs:87:9
   |
25 | /         select! {
26 | |             msg = msg_future => println!("Got a message: {}", msg),
27 | |             _ = timeout => {
28 | |                 println!("Getting impatient!");
29 | |                 continue;
30 | |             },
31 | |         };
   | |__________^ doesn't have a size known at compile-time
   |
   = help: the trait `std::marker::Sized` is not implemented for `[_]`
   = note: to learn more, visit <https://doc.rust-lang.org/book/ch19-04-advanced-types.html#dynamically-sized-types-and-the-sized-trait>
   = note: all local variables must have a statically known size
   = help: unsized locals are gated as an unstable feature
   = note: this error originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)

I'm a little lost as to what is wrong with the code. Also the code did work with version "0.3.0-alpha.10", but I rewrote it for alpha 11 and can't figure these errors out.

Any help would be appreciated.

[taiki-e]

Until #1405 is merged, we should be able to avoid this error by importing select! macro from futures.