Cut type_alias_impl_trait feature flag

tarpc/examples/pubsub.rs

@@ -4,8 +4,6 @@
 // license that can be found in the LICENSE file or at
 // https://opensource.org/licenses/MIT.
 
-#![feature(type_alias_impl_trait)]
-
 use futures::{
     future::{self, Ready},
     prelude::*,
@@ -16,6 +14,7 @@ use std::{
     collections::HashMap,
     io,
     net::SocketAddr,
+    pin::Pin,
     sync::{Arc, Mutex},
     thread,
     time::Duration,
@@ -87,7 +86,7 @@ impl Publisher {
 }
 
 impl publisher::Publisher for Publisher {
-    type BroadcastFut = impl Future<Output = ()>;
+    type BroadcastFut = Pin<Box<dyn Future<Output = ()> + Send>>;
 
     fn broadcast(self, _: context::Context, message: String) -> Self::BroadcastFut {
         async fn broadcast(
@@ -103,10 +102,10 @@ impl publisher::Publisher for Publisher {
             }
         }
 
-        broadcast(self.clients.clone(), message)
+        broadcast(self.clients.clone(), message).boxed()
     }
 
-    type SubscribeFut = impl Future<Output = Result<(), String>>;
+    type SubscribeFut = Pin<Box<dyn Future<Output = Result<(), String>> + Send>>;
 
     fn subscribe(self, _: context::Context, id: u32, addr: SocketAddr) -> Self::SubscribeFut {
         async fn subscribe(
@@ -122,10 +121,12 @@ impl publisher::Publisher for Publisher {
             Ok(())
         }
 
-        subscribe(Arc::clone(&self.clients), id, addr).map_err(|e| e.to_string())
+        subscribe(Arc::clone(&self.clients), id, addr)
+            .map_err(|e| e.to_string())
+            .boxed()
     }
 
-    type UnsubscribeFut = impl Future<Output = ()>;
+    type UnsubscribeFut = Pin<Box<dyn Future<Output = ()> + Send>>;
 
     fn unsubscribe(self, _: context::Context, id: u32) -> Self::UnsubscribeFut {
         eprintln!("Unsubscribing {}", id);
@@ -136,7 +137,7 @@ impl publisher::Publisher for Publisher {
                 id, &*clients
             );
         }
-        future::ready(())
+        future::ready(()).boxed()
     }
 }
 

tarpc/examples/server_calling_server.rs

@@ -4,14 +4,12 @@
 // license that can be found in the LICENSE file or at
 // https://opensource.org/licenses/MIT.
 
-#![feature(type_alias_impl_trait)]
-
 use crate::{add::Add as AddService, double::Double as DoubleService};
 use futures::{
     future::{self, Ready},
     prelude::*,
 };
-use std::io;
+use std::{io, pin::Pin};
 use tarpc::{
     client, context,
     server::{Handler, Server},
@@ -50,7 +48,7 @@ struct DoubleServer {
 }
 
 impl DoubleService for DoubleServer {
-    type DoubleFut = impl Future<Output = Result<i32, String>> + Send;
+    type DoubleFut = Pin<Box<dyn Future<Output = Result<i32, String>> + Send>>;
 
     fn double(self, _: context::Context, x: i32) -> Self::DoubleFut {
         async fn double(mut client: add::AddClient, x: i32) -> Result<i32, String> {
@@ -60,7 +58,7 @@ impl DoubleService for DoubleServer {
                 .map_err(|e| e.to_string())
         }
 
-        double(self.add_client.clone(), x)
+        double(self.add_client.clone(), x).boxed()
     }
 }