Really not a fan of this approach. Makes the order of operations extremely weird. I would much prefer having super blocks that are explicitly inserted in the above scope. I.e. this:

tokio::task::spawn(async move {
    do_something_else_with(
        super { self.some_a.clone() },
        super { self.some_a.clone() },
        super { self.some_a.clone() },
    )
});

Would desugar to:

tokio::task::spawn({
    let first_block = { self.some_a.clone() };
    let second_block = { self.some_a.clone() };
    let third_block = { self.some_a.clone() };
    async move {
        do_something_else_with(
            first_block,
            second_block,
            third_block,
        )
    }
});

Only problem is if the clone is inside another block... but perhaps you could do super super { ... }? But that sort of gets crazy and makes it very hard to read again.

[–] Starfighter@discuss.tchncs.de 3 points 1 month ago (1 children)

I was under the impression that the compiler already optimizes out a lot of clones where the clone is primarily used to satisfy the borrow checker. Is that not the case?

[–] SorteKanin@feddit.dk 3 points 1 month ago* (last edited 1 month ago)

I would say depends but generally I would think not? I mean say you clone a string because you move it in one place and also need to borrow it in another place. So you clone to avoid the borrow checker erroring out on that. As far as I know, there will be two different strings created with separate allocations and all (but I could be wrong).