add future_ext

Author: yoshuawuyts

src/future/futures_ext.rs

@@ -0,0 +1,43 @@
+use crate::future::Join;
+use crate::future::Race;
+use futures_core::Future;
+use std::future::IntoFuture;
+
+use super::join::tuple::Join2;
+use super::race::tuple::Race2;
+
+/// An extension trait for the `Future` trait.
+pub trait FutureExt: Future {
+    /// Wait for both futures to complete.
+    fn join<S2>(self, other: S2) -> Join2<Self, S2::IntoFuture>
+    where
+        Self: Future + Sized,
+        S2: IntoFuture;
+
+    /// Wait for the first future to complete.
+    fn race<T, S2>(self, other: S2) -> Race2<T, Self, S2::IntoFuture>
+    where
+        Self: Future<Output = T> + Sized,
+        S2: IntoFuture<Output = T>;
+}
+
+impl<F1> FutureExt for F1
+where
+    F1: Future,
+{
+    fn join<F2>(self, other: F2) -> Join2<Self, F2::IntoFuture>
+    where
+        Self: Future + Sized,
+        F2: IntoFuture,
+    {
+        Join::join((self, other))
+    }
+
+    fn race<T, S2>(self, other: S2) -> Race2<T, Self, S2::IntoFuture>
+    where
+        Self: Future<Output = T> + Sized,
+        S2: IntoFuture<Output = T>,
+    {
+        Race::race((self, other))
+    }
+}

src/future/mod.rs

@@ -68,11 +68,13 @@
 //! - `future::RaceOk`: wait for the first _successful_ future in the set to
 //! complete, or return an `Err` if *no* futures complete successfully.
 //!
+pub use futures_ext::FutureExt;
 pub use join::Join;
 pub use race::Race;
 pub use race_ok::RaceOk;
 pub use try_join::TryJoin;
 
+mod futures_ext;
 pub(crate) mod join;
 pub(crate) mod race;
 pub(crate) mod race_ok;