Implement Default trait for OptionFuture (#2471)

EFanZh · taiki-e · commit ccb59ce5e14b · 2021-08-30T19:05:30.000+09:00
This provides an easy way to create empty `OptionFuture`s.
diff --git a/futures-util/src/future/option.rs b/futures-util/src/future/option.rs
@@ -31,6 +31,12 @@ pin_project! {
     }
 }
 
+impl<F> Default for OptionFuture<F> {
+    fn default() -> Self {
+        Self { inner: None }
+    }
+}
+
 impl<F: Future> Future for OptionFuture<F> {
     type Output = Option<F::Output>;
 

Original file line number	Diff line number	Diff line change
`@@ -31,6 +31,12 @@ pin_project! {`
`31`	`31`	`}`
`32`	`32`	`}`
`33`	`33`
	`34`	`+impl<F> Default for OptionFuture<F> {`
	`35`	`+ fn default() -> Self {`
	`36`	`+ Self { inner: None }`
	`37`	`+ }`
	`38`	`+}`
	`39`	`+`
`34`	`40`	`impl<F: Future> Future for OptionFuture<F> {`
`35`	`41`	`type Output = Option<F::Output>;`
`36`	`42`