Operator[][] overload

Question

Is it possible to overload [] operator twice? To allow, something like this: function[3][3](like in a two dimensional array).

If it is possible, I would like to see some example code.

Answer 1

You can overload operator[] to return an object on which you can use operator[] again to get a result.

class ArrayOfArrays { public:     ArrayOfArrays() {         _arrayofarrays = new int*[10];         for(int i = 0; i < 10; ++i)             _arrayofarrays[i] = new int[10];     }      class Proxy {     public:         Proxy(int* _array) : _array(_array) { }          int operator[](int index) {             return _array[index];         }     private:         int* _array;     };      Proxy operator[](int index) {         return Proxy(_arrayofarrays[index]);     }  private:     int** _arrayofarrays; }; 

Then you can use it like:

ArrayOfArrays aoa; aoa[3][5]; 

This is just a simple example, you'd want to add a bunch of bounds checking and stuff, but you get the idea.

Answer 2

For a two dimensional array, specifically, you might get away with a single operator[] overload that returns a pointer to the first element of each row.

Then you can use the built-in indexing operator to access each element within the row.