Question

I’m a C++ noob programmer… (I usually use Java) and now I’ve got some problems with pointers, references and vectors…

I need to extract an Object from vector<Object> objects and for simplicity i would like to store his reference in another object cause I need to edit some parameters inside of it many times

this is the code i’ve written so far:

Object myObject = getMyObject(id, objects); 

and getMyObject simply implements a for cycle which finds the right object with the right id and it returns it with return objects[i]

but if I understood right, this method duplicates the objects! so, in myObject there’s a completely different Object, is it right?

How should I do??

Thank you very much!

Answer 1

You’re right. What you should do is have the get function return a reference:

Object & getMyObject(int id, std::vector<Object> & objects)
{
    // ... find ...
    return objects[i];
}

Then bind this to another reference in your user code:

Object & theobject = getMyObject(12, all_objects);

Now you modify the contained element directly via the reference theobject.

If you don’t want/need to modify the object, just inspect them, you should make the reference (as well as the container) const:

Object const & getMyObject(int id, std::vector<Object> const & objects);