fn call(&self, req: Request) -> Future = async {
    // ...
}

Honestly, that's not much better than the already working (but admittedly weird looking)

fn call(&self, req: Request) -> impl Future { async {
    // ...
}}

But I do agree with the gist of the article. Time to get out the 🍿 and hop on over to r/rust.

Edit: Lemmy's markdown parser doesn't appear to like ampersands in code fences, or angle brackets…

Edit2: After reading u/cramertj's response, it looks like lifetimes would complicate what I wrote above significantly. So… yeah, thanks for all the work, Sean and Tyler, it's appreciated. 🙂