[jihiggins]

idk there are a lot of uses for it

    let dx = {
        let prev_x = x;
        x = get_x();
        x - prev_x
    };

often, it's slightly better cpp style scoping blocks if nothing else? there are tons of other little QoL things it enables though, but they're all going to be little ergonomics things that only seem worth it if you've used the language for awhile

[masklinn]

Also common to set up "capture clauses" for lambdas as Rust does not have that in the language, IME most common with threads:

    spawn({
        let a = a.clone();
        let b = &b;
        move || {
            // do something with the a you cloned and the b you borrowed
        }
    })