struct ABC {
mut:
    s string
}

fn test_shared_option() {
    shared abc := foo() or { panic('scared') }
    rlock abc {
        println(abc)
        assert abc.s == 'hello'
    }
}

fn foo() ?ABC {
    mut a := ABC{}
    a.bar()?
    return a
}

fn (mut a ABC) bar() ? {
    a.s = 'hello'
    println(a.s)
}