Should boost::ptr_vector be used in place std::vector all of the time?
boost, c++, smart-pointers, vector
Solution
You should only use owning smart pointers and pointer containers where there's clear transfer of ownership. It doesn't matter if the object is temporary or not - all that matters is whether it has ownership or not (and, therefore, whether the previous owner relinquishes ownership).
If you create a temporary vector of pointers just to pass it to some other function, and the original `ptr_vector` still references all those objects, there's no ownership transfer, and therefore you should use plain `vector` for the temporary object - just as you'd use a raw pointer to pass a single object from `ptr_vector` to a function that takes a pointer, but doesn't store it anywhere.
Problem
Just a conceptual question that I've been running into. In my current project it feels like I am over-using the boost `smart_ptr` and `ptr_container` libraries. I was creating `boost::ptr_vectors` in many different objects and calling the transfer() method to move certain pointers from one `boost::ptr_vector` to another. It is my understanding that it is important to clearly show ownership of heap allocated objects. My question is, would it be desirable to use these boost libraries to create heap-allocated members that belong to an object but then use normal pointers to these members via `get()` when doing any processing. For example... A game might have a collection of Tiles that belong to it. It might make sense to create these tiles in a `boost::ptr_vector`. When the game is over these tiles should be automatically freed. However if I want to put these Tiles in a Bag object temporarily, should I create another `boost::ptr_vector` in the bag and transfer the Game's Tiles to the Bag via `transfer()` or should I create a `std::vector<Tile*>` where the Tiles*'s reference the Tiles in the Game and pass that to the Bag? Thanks. **Edit I should point out that in my example The Game would have a Bag object as a member. The Bag would only be filled with Tiles the game owns. So the Bag would not exist without the Game.