});
            a.map(Activation::getOs).ifPresent(oa -> {
                Interpolation nt = new Interpolation(oa, interpolator::interpolate);
                nt.performFor(oa.getArch(), "arch", oa::setArch);
                nt.performFor(oa.getFamily(), "family", oa::setFamily);
                nt.performFor(oa.getName(), "name", oa::setName);
                nt.performFor(oa.getVersion(), "version", oa::setVersion);

        root.map(Activation::getOs).ifPresent(oa -> {
            stk.push(new ActivationFrame("os", Optional.of(oa)));
            stk.push(new ActivationFrame("arch", Optional.empty()));
            validator.accept(oa.getArch());
            stk.peek().location = "family";
            validator.accept(oa.getFamily());
            stk.peek().location = "name";
            validator.accept(oa.getName());