async_fn_traits
See Also: fn_traits
The async_fn_traits
feature allows for implementation of the AsyncFn*
traits
for creating custom closure-like types that return futures.
The main difference to the Fn*
family of traits is that AsyncFn
can return a future
that borrows from itself (FnOnce::Output
has no lifetime parameters, while AsyncFnMut::CallRefFuture
does).