Question

Given:

class example
{
    public:
        std::vector<std::vector<int>> a;
        int b;
}

func()
{
    example e;
    ... // populate e

I could then use examples members like so.

    int n = e.b;
    int n2 = e.a[2][3];

However, could I alternatively override the [ ] operator such that.

    int n = e.b;
    int n2 = e[2][3];
}

?

edit: Sorry, the example is now fixed.

Answer 1

What you could do is overload the access operator and delegate it to the vector:

class example
{
    public:
        std::vector<std::vector<int>> a;
        int b;

        const std::vector<int>& operator[](std::size_t i) const
        {
            return a[i];
        }
        std::vector<int>& operator[](std::size_t i)
        {
            return a[i];
        }
};

The first [] will then return a reference to a‘s respective element, on which the second [] will be used.