SOURCE

{
    let a,b,rest
    [a, b] = [1, 2]
    console.log(a,b)
    console.log('========')
}

{
    let a, b, rest
    [a,b,...rest] = [1,2,3,4,5,6,7]
    console.log(a)
    console.log(b)
    console.log(rest)
    console.log('========')
}

{
    let a, b;
    ({a, b} = {a:1, b:2})
    console.log(a)
    console.log(b)
    console.log('========')
}

{
    let a, b, c, rest
    [a, b, c, d=4] = [1, 2]
    console.log(a)
    console.log(b)
    console.log(c)
    console.log(d)
    console.log('========')
}

{
    let a = 1;
    let b = 2;
    [a, b] = [b, a];
    console.log(a,b);
    console.log('========');
}

{
    function f(){
        return [1, 2]
    }
    let a, b;
    [a, b] = f();
    console.log(a,b)
    console.log('========');
}

{
    function f() {
        return [1, 2, 3, 4, 5]
    }
    let a,b,c;
    [a,,,b] =f()
    console.log(a,b)
    console.log('========');
}

{
    function f() {
        return [1, 2, 3, 4, 5]
    }
    let a,b,c;
    [a,...b] =f()
    console.log(a)
    console.log(b)
    console.log('========');
}