dynify now has a macro for heapless async traits

Hello, fellow Rustaceans!

dynify is another crate to make async traits dyn compatible. The main selling point is that dynify doesn't require async methods to return a boxed Future.

Recently, I added an attribute macro #[dynify] to make using dynify as straightforward as #[async_trait]. Basically, you only need to place #[dynify] to the target trait, and it will generate a dyn compatible variant for that trait:

#[dynify::dynify]
trait AsyncRead {
    async fn read_to_string(&mut self) -> String;
}

To invoke an async method, you need to choose where its return value is allocated, stack or heap:

async fn dynamic_dispatch(reader: &mut dyn DynAsyncRead) {
    let mut stack = [MaybeUninit::<u8>::uninit(); 16];
    let mut heap = Vec::<MaybeUninit<u8>>::new();
    // Initialize the trait object on the stack if not too large, otherwise the heap
    let fut = reader.read_to_string().init2(&mut stack, &mut heap);
    let content = fut.await;
    // ...
}