diff --git a/src/ch17-05-traits-for-async.md b/src/ch17-05-traits-for-async.md index 7f2b66bd4d..547cbe2c44 100644 --- a/src/ch17-05-traits-for-async.md +++ b/src/ch17-05-traits-for-async.md @@ -198,7 +198,7 @@ Directly awaiting a future with `await` pins the future implicitly. That’s why we don’t need to use `pin!` everywhere we want to await futures. However, we’re not directly awaiting a future here. Instead, we construct a new -future, JoinAll, by passing a collection of futures to the `join_all` function. +future, `JoinAll`, by passing a collection of futures to the `join_all` function. The signature for `join_all` requires that the types of the items in the collection all implement the `Future` trait, and `Box` implements `Future` only if the `T` it wraps is a future that implements the `Unpin` trait.