Serializing only part of an std::vector with Boost serialization

Question

I have a large std::vector<X> where X is a structure with a serialize function for Boost.

I would like to serialize only part (a contiguous segment) of this vector in such a way that deserializing the result would give me an std::vector<X> with just the elements I serialized.

I can provide iterators pointing to the beginning and the end of the segment I want to serialize, or I can provide begin and end indices. Is there a way to do that without creating a smaller vector and copying the desired elements in it?

Note that I am using binary archives so any solution that would work only for this type of archive is fine.

How would you serialize using iterators? (I mean, aside from doing a loop myself to serialize elements one by one) — sunmat, Jan 30 '20 at 14:02
You could try it with boost ranges, but i really don't see the problem with writing one for loop (or alternatively `std::for_each`). — n314159, Jan 30 '20 at 14:18

score 0 · Answer 1 · answered Jan 30 '20 at 14:58

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Using std::valarray(https://en.cppreference.com/w/cpp/numeric/valarray) is the way to go here. Coincidentally, boost serialization supports valarray as well, so you're good to go. Here's a comparison btw std::vector and std::valarray for clarity's sake: C++ valarray vs. vector

answered Jan 30 '20 at 14:58

theWiseBro

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Since you are already suggesting data copy, what value would it add except more complexity? – Tanveer Badar Jan 30 '20 at 16:48
Indeed, converting the original std::vector to an std::valarray would produce a copy in the first place. – sunmat Jan 31 '20 at 09:48

Serializing only part of an std::vector with Boost serialization

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