getInserted().add(new Element<T>(element));
            return true;
        } else {
            return false;
        }
    }

    @Override
    public boolean addRealized(T value) {
        markDuplicates(value);
        return true;
    }

    @Override
    protected void clearCachedElement(Element<T> element) {
        boolean wasRealized = element.isRealized();

        }
        return element;
    }

    private void doAddRealized(T value) {
        if (addRealized(value) && pendingAddedAction != null) {
            pendingAddedAction.execute(value);
        }
    }

    abstract boolean addRealized(T element);

    @Override
    public boolean removePending(ProviderInternal<? extends T> provider) {

    }

    @Override
    public boolean add(T element) {
        modCount++;
        return getInserted().add(new Element<T>(element));
    }

    @Override
    public boolean addRealized(T value) {
        return true;
    }

    @Override
    public boolean addPending(ProviderInternal<? extends T> provider) {
        modCount++;
        return addPendingElement(cachingElement(provider));
    }