code from the above playground:

struct NoCopy;

fn this_one_compiles() {
    let a = Some(5);
    let b = Some(NoCopy);
    
    loop {
        if let Some(a) = a && let Some(b) = b {
            break (a, b)
        }
    };
}

fn then_why_doesnt_this_one_compile() {
    let a = Some(NoCopy);
    let b = Some(NoCopy);
    
    loop {
        if let Some(a) = a && let Some(b) = b {
            break (a, b)
        }
    };
}

the first function compiles and shows that rust understands that if let Some(foo) = opt { break foo },
the second function shows that it doesn't.
my guess is that only the last let can consume, but why?

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