Can I store std::shared_ptr to ROOT file?

ROOT
1

Dear experts

Sorry if this is a duplicated question! I have two classes:

class A : public TObject{
//some parameters
};

class AContainer : public TObject, public std::vector<COMET::IDriftElectron*>{
//some mathods
};

Can I change the std::vector<COMET::IDriftElectron*> structure to std::vector<std::shared_ptr<COMET::IDriftElectron>>? Can I still store them into a ROOT TTree and TFile?

ROOT Version: 6.24.02
Platform: Linux
Compiler: gcc11

2

Hi,

The persistification of shared_ptrs, e.g. as data members, is not supported because of the semantic of the very class.
If I may, I would also discourage the design of classes inheriting from STL containers, and opt perhaps for encapsulation (this is a suggestion which is independent from ROOT).

Best,
Danilo

3

Thank you for answering! Could you please tell more that why it’s not suggested using STL containers?

4

You can and should use STL containers.

What is not recommended is designing a class inheriting from a STL containers (using composition is usually a better pattern).

You can find several writeups on the issue including Can We Inherit STL Containers? - GeeksforGeeks or https://www.researchgate.net/post/I-really-want-to-understand-if-there-is-any-reason-why-one-should-not-inherit-from-the-stl-vector-class-in-c

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