or use `IntoIterator::into_iter(..)` instead of `.into_iter()` to explicitly iterate by value

lint_async_fn_in_trait = use of `async fn` in public traits is discouraged as auto trait bounds cannot be specified

.note = you can suppress this lint if you plan to use the trait locally, for concrete types, or do not care about auto traits like `Send` on the `Future`

.note = you can suppress this lint if you plan to use the trait only in your own code, or do not care about auto traits like `Send` on the `Future`

.suggestion = you can alternatively desugar to a normal `fn` that returns `impl Future` and add any desired bounds such as `Send`

lint_atomic_ordering_fence = memory fences cannot have `Relaxed` ordering

/// }

///

/// fn test<T: Trait>(x: T) {

/// fn is_send<T: Send>(_: T) {}

/// is_send(x.method()); // Not OK.

/// fn spawn<T: Send>(_: T) {}

/// spawn(x.method()); // Not OK.

/// }

/// ```

///

/// }

/// ```

///

/// Conversely, if the trait is used only locally, if only concrete types

/// that implement the trait are used, or if the trait author otherwise

/// does not care that the trait will not promise that the returned

/// [`Future`] implements any [auto traits] such as [`Send`], then the

/// lint may be suppressed.

/// Conversely, if the trait is used only locally, if it is never used in

/// generic functions, or if it is only used in single-threaded contexts

/// that do not care whether the returned [`Future`] implements [auto traits]

/// such as [`Send`], then the lint may be suppressed.

///

/// [`Future`]: https://doc.rust-lang.org/core/future/trait.Future.html

/// [`Send`]: https://doc.rust-lang.org/core/marker/trait.Send.html

LL | async fn not_send();

| ^^^^^

|

= note: you can suppress this lint if you plan to use the trait locally, for concrete types, or do not care about auto traits like `Send` on the `Future`

= note: you can suppress this lint if you plan to use the trait only in your own code, or do not care about auto traits like `Send` on the `Future`

note: the lint level is defined here

--> $DIR/warn.rs:4:9

|