realm_set_collection(obj1.get(), foo_any_col_key, RLM_COLLECTION_TYPE_LIST);
realm_value_t value;
realm_get_value(obj1.get(), foo_any_col_key, &value);
auto list = cptr_checked(realm_get_list(obj1.get(), foo_any_col_key));
realm_list_insert_collection(list.get(), 0, RLM_COLLECTION_TYPE_LIST);
auto n_list = cptr_checked(realm_list_get_list(list.get(), 0));
realm_list_insert(n_list.get(), 0, rlm_str_val("Test1"));
realm_list_set_collection(list.get(), 0, RLM_COLLECTION_TYPE_DICTIONARY);

//the accessor has become invalid. Trying to use for inserting into the list should fail, with some exception be thrown.
realm_list_insert(n_list.get(), 1, rlm_str_val("Test2"));

bool Lst<Mixed>::init_from_parent(bool allow_create) const
{
    if (!m_tree) {
        m_tree.reset(new BPlusTreeMixed(get_alloc()));
        const ArrayParent* parent = this;
        m_tree->set_parent(const_cast<ArrayParent*>(parent), 0);
    }
    try {
        auto ref = Base::get_collection_ref();
        if (ref) {
            m_tree->init_from_ref(ref);
        }
        else {
            if (!allow_create) {
                m_tree->detach();
                return false;
            }

            // The ref in the column was NULL, create the tree in place.
            m_tree->create();
            REALM_ASSERT(m_tree->is_attached());
        }
    }
    catch (...) {
        m_tree->detach();
        return false;
    }

    return true;
}

ref_type Lst<Mixed>::get_collection_ref(Index index, CollectionType type) const
{
    auto ndx = m_tree->find_key(mpark::get<int64_t>(index));
    if (ndx != realm::not_found) {
        auto val = get(ndx);
        if (val.is_null() || !val.is_type(DataType(int(type)))) {
            throw IllegalOperation("Not proper collection type");
        }
        return val.get_ref();
    }

    return 0;
}