Question

Sorry if this has been asked before, but I can’t find a clear enough answer.

What is the correct way to provide public read-only access to an array member in C++?

if i have a class like the following:

   
class Particle
{
    double _position[10];

public:
    double* get_position()
    {
       return _position;
    }
};
   

I guess is really bad to return a pointer to the array, since that means it can be changed at
any time outside of the class, is it enough to return a const pointer instead?

I have seen other questions about the use of arrays in C++, and how is a better option to use vectors, nevertheless I’m really curious about this issue.

As you can see I’m only a C++ noob, sorry if this is a stupid question.

P.D. Sorry for my bad English.

Answer 1

You can return a const pointer:

class Particle
{
    double _position[10];

public:
    const double* get_position() const
    {
       return _position;
    }
};

Note that I’ve also made the member-function const (the second const), to tell the compiler that this member-function may be called on const Particle instances.

Note: as you’ve already mentioned, a better solution is to use STL vectors and so on…