public notExist;
class foo {
    public var vFoo;
    public const cFoo = 3;
}

foo bar();

proc main()
{
    "foo.vFoo readonly: ", oadl::readonly(foo,public::vFoo), '\n';
    "bar.vFoo readonly: ", oadl::readonly(bar,public::vFoo), '\n';
    "bar.cFoo readonly: ", oadl::readonly(bar,public::cFoo), '\n';
    "bar.notExist readonly: ", oadl::readonly(bar,public::notExist), '\n';
}