make AbstractObject move constructible and move assignable

[untereiner]

Is your feature request related to a problem? Please describe.
I would like to transform the unordered_map from getDataObjects. However it is not possible to process it because the object behind of std::unique_ptr is not movable.

Describe the solution you'd like
Make AbstractObject movable or remove the unique_ptr

Describe alternatives you've considered
n.a.

Additional context
n.a.

[philippeVerney]

Hi Lionel,

The ownership of an AbstractObject is managed by the DataObjectRepository. So, I think I should even make AbstractObject non copyable (and still non movable).
Which kind of transform is not allowed? Could you share some few lines of codes?

Removing unique_ptr would somehow lead to the same result than getDataObjectsGroupedByDataType() (grouping by datatype instead of grouping by UUID), is it not OK with you?
You also have the option to loop on getUuids and then getDataObjectByUuid

getDataObjects returns unique_ptr because it is a direct (const) reference on the class member to get most of performance.

[untereiner]

Hi Philippe,

I wanted to write something like this:

std::vector<std::vector<std::unique_ptr<COMMON_NS::AbstractObject>>> DataObjects;
auto mapOfObjects = repo->GetDataObjects();
std::transform(std::move_iterator(mapOfObjects.begin()), std::move_iterator(mapOfObjects.end()), std::back_inserter(DataObjects), [](std::pair<std::string, std::vector<std::unique_ptr<COMMON_NS::AbstractObject>>>&& entry)  { return std::move(entry.second); });

I understand that's a reference to the most important class member. I shouldn't touch it.
I can do something like:

auto uuids  = repo->getUuids();
std::vector<COMMON_NS::AbstractObject> DataObjects;
for(const auto& uuid : uuids)
{
     DataObjects.push_back(repo->getDataObjectByUuidAndVersion(uuid, version))
}

Thank you!

[philippeVerney]

Yes, the alternative using getUuids would definitely work!
For performance reason (if it is important for you), I think you can still use repo->GetDataObjects() but :

• get the raw pointers by yourself from the unique_ptrs
• copy them in a new vector.

Something like

        std::vector<std::vector<COMMON_NS::AbstractObject*>> DataObjects;
	for (const auto& entry : repo.getDataObjects()) {
		std::vector<COMMON_NS::AbstractObject*> tmp;
		for (auto& entry2 : entry.second) {
			tmp.push_back(entry2.get());
		}
		DataObjects.push_back(tmp);
	}

Indeed, getDataObjectByUuidAndVersion will perform a find in the map at each loop increment which would be imho less performant than a (light)transform and copy.

I keep this ticket opened in order to make AbstractObject non copyable as it should be (and if I have time, I also should make the destructor private to avoid that FESAPI users may manage the lifetime of AbstractObject by themselves)

[philippeVerney]

Closed after 3538429