use \'asyc_trait in TryFutureExt

Author: Roman Proskuryakov

src/future.rs

@@ -45,51 +45,17 @@ pub trait FutureExt: Future {
     }
 }
 
-#[async_trait]
-pub trait TryFuture: Future {
-    type Ok;
-    type Error;
-
-    async fn and_then<U, F, FutB>(self, f: F) -> Result<U, Self::Error>
-        where F: FnOnce(Self::Ok) -> FutB + Send,
-              FutB: Future<Output = Result<U, Self::Error>> + Send,
-              Self: Sized;
-
-    async fn or_else<U, F, FutB>(self, f: F) -> Result<Self::Ok, U>
-        where F: FnOnce(Self::Error) -> FutB + Send,
-              FutB: Future<Output = Result<Self::Ok, U>> + Send,
-              Self: Sized;
-
-    async fn map_ok<U, F>(self, f: F) -> Result<U, Self::Error>
-        where F: FnOnce(Self::Ok) -> U + Send,
-              Self: Sized;
-
-    async fn map_err<U, F>(self, f: F) -> Result<Self::Ok, U>
-        where F: FnOnce(Self::Error) -> U + Send,
-              Self: Sized;
-
-    async fn err_into<U>(self) -> Result<Self::Ok, U>
-        where Self::Error: Into<U>,
-              Self: Sized;
-
-    async fn unwrap_or_else<F>(self, f: F) -> Self::Ok
-        where F: FnOnce(Self::Error) -> Self::Ok + Send,
-              Self: Sized;
-}
+impl<T, E, Fut: ?Sized> TryFutureExt<T, E> for Fut where Fut: Future<Output = Result<T, E>> {}
 
 #[async_trait]
-impl<T, E, Fut> TryFuture for Fut
-    where Fut: ?Sized + Future<Output = Result<T, E>> + Send,
-          T: Send + 'static,
-          E: Send + 'static,
-{
-    type Ok = T;
-    type Error = E;
+pub trait TryFutureExt<T, E>: Future<Output = Result<T, E>> {
 
-    async fn and_then<U, F, FutB>(self, f: F) -> Result<U, Self::Error>
-        where F: FnOnce(Self::Ok) -> FutB + Send,
-              FutB: Future<Output = Result<U, Self::Error>> + Send,
-              Self: Sized
+    async fn and_then<U, F, FutB>(self, f: F) -> Result<U, E>
+        where F: FnOnce(T) -> FutB + Send,
+              FutB: Future<Output = Result<U, E>> + Send,
+              Self: Sized,
+              T: Send + 'async_trait,
+              E: Send + 'async_trait,
     {
         match self.await {
             Ok(ok) => {
@@ -100,10 +66,12 @@ impl<T, E, Fut> TryFuture for Fut
         }
     }
 
-    async fn or_else<U, F, FutB>(self, f: F) -> Result<Self::Ok, U>
-        where F: FnOnce(Self::Error) -> FutB + Send,
-              FutB: Future<Output = Result<Self::Ok, U>> + Send,
+    async fn or_else<U, F, FutB>(self, f: F) -> Result<T, U>
+        where F: FnOnce(E) -> FutB + Send,
+              FutB: Future<Output = Result<T, U>> + Send,
               Self: Sized,
+              T: Send + 'async_trait,
+              E: Send + 'async_trait,
     {
         match self.await {
             Ok(ok) => Ok(ok),
@@ -114,30 +82,38 @@ impl<T, E, Fut> TryFuture for Fut
         }
     }
 
-    async fn map_ok<U, F>(self, f: F) -> Result<U, Self::Error>
-        where F: FnOnce(Self::Ok) -> U + Send,
-              Self: Sized
+    async fn map_ok<U, F>(self, f: F) -> Result<U, E>
+        where F: FnOnce(T) -> U + Send,
+              Self: Sized,
+              T: Send + 'async_trait,
+              E: Send + 'async_trait,
     {
         self.await.map(f)
     }
 
-    async fn map_err<U, F>(self, f: F) -> Result<Self::Ok, U>
-        where F: FnOnce(Self::Error) -> U + Send,
+    async fn map_err<U, F>(self, f: F) -> Result<T, U>
+        where F: FnOnce(E) -> U + Send,
               Self: Sized,
+              T: Send + 'async_trait,
+              E: Send + 'async_trait,
     {
         self.await.map_err(f)
     }
 
-    async fn err_into<U>(self) -> Result<Self::Ok, U>
-        where Self::Error: Into<U>,
+    async fn err_into<U>(self) -> Result<T, U>
+        where E: Into<U>,
               Self: Sized,
+              T: Send + 'async_trait,
+              E: Send + 'async_trait,
     {
         self.await.map_err(Into::into)
     }
 
-    async fn unwrap_or_else<F>(self, f: F) -> Self::Ok
-        where F: FnOnce(Self::Error) -> Self::Ok + Send,
+    async fn unwrap_or_else<F>(self, f: F) -> T
+        where F: FnOnce(E) -> T + Send,
               Self: Sized,
+              T: Send + 'async_trait,
+              E: Send + 'async_trait,
     {
         self.await.unwrap_or_else(f)
     }