private final ModelReference<?> mappedSubject;
            private final List<ModelReference<?>> inputs;
            private final MethodRuleAction action;
            private final Factory<? extends T> factory;

        }
    }

    @Override
    public <T> void bind(ModelReference<T> subject, ModelActionRole role, ModelAction mutator) {
        bindInternal(subject, role, mutator);
    }

    private <T> RuleBinder bindInternal(ModelReference<T> subject, ModelActionRole role, ModelAction mutator) {
        BindingPredicate mappedSubject = mapSubject(subject, role);