Attribute Macro async_auto_traits::set

#[set]

Set auto traits for this async fns return type.

Only Send and Sync are currently supported.

This adds an assertion that those auto traits are valid for the async fns body, i.e. it does not invoke any unsafe code and will produce a compile error when the auto traits are not satisfied.

Example

#[async_auto_traits::set(Send + Sync)]
async fn foo() {}

Planned features

Writing !Trait should allow you to explicitly opt out of Send or Sync if it would otherwise be inferred. This is for when you don't want to promise too much about the future returned by a function to avoid future breaking changes.

Example

#[async_auto_traits::set(Send + !Sync)]
async fn foo() {}