return a set container

[Jonas Wingren]

Hi!
Just wanted to know if there is an easy and non memory heavy way of returning a set container that cannot alter the original container (or a reference to it or pointer, you get the idea)

//The elements I want to create a get function for
std::set<Order> m_SellOrders, m_BuyOrders;

// current prototype
std::set<Order> getSellOrders(){return std::set<Order> temp = m_SellOrders;};

but I'm guessing the prototype is kinda heavy on memory, any tips?

[firedraco]

Return a const reference to it if you don't ever need to change it.

[Jonas Wingren]

that easy huh?

I just thought that a const reference just refers to the same element.

But the element itself still could be altered or am I way off?

[IceThatJaw]

Something like this maybe..

struct Foo
{
const set<Order>& GetSet() { return m_SellOrders; }
set<Order> m_SellOrders;
};

[firedraco]

int x;
int copy = x; //a copy of x, can be modified independently of x
const int c_int = x; //a copy of x, can't be modified, independent of x
int& ref_int = x; //alias to x, meaning this is basically a different way to refer to x
const int& cref_int = x; //alias to x, cannot be modified, but if x changes it will change 

Does this clear it up?

[Jonas Wingren]

Yes it does, thanks a lot. Now I learnt something very useful :D

Thanks!