struct Foo {
mut:
    bar shared [10]bool
}

fn test_main() {
    mut a := Foo{
        bar: [10]bool{}
    }
    lock a.bar {
        a.bar[0] = true
        a.bar[1] = false
    }
    rlock a.bar {
        assert a.bar[0] == true
        assert a.bar[1] == false
    }
}