operator overloading

[liondancer]

Object & operator[]( int index )
    {
                                                     #ifndef NO_CHECK
        if( index < 0 || index >= currentSize )
            throw ArrayIndexOutOfBounds( );
                                                     #endif
        return objects[ index ];
    }

I was wondering that does the & mean in the line of code?

[Breadman]

I was wondering that does the & mean in the line of code?

It returns the object at the current index, not a copy of it.

int a = 5;
int &b = a; // b and a are the same
int c = a; // c has the value of a

b = 64; // a and b are 64
c = 43; // only c is 43 

if you didnt have the ampersand you would return a copy and it couldnt be modified.

class Array
{
    int num[3];
public:
    Array()
    {
        num[0] = 65;
        num[1] = 315;
        num[2] = 647;
    }

    int& operator[](int index)
    {
        return num[index];
    }
    const int getNumber(int index)
    {
        return num[index];
    }
};

int main(int argc, char *argv[])
{
    Array arr;
    arr[0] = 5; // :)
    arr.getNumber(0) = 3; // error cant edit the copy :/
    std::cout << arr[0];
}