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 pos

Answer 1

It 'll be great if you can let me know what function, function[x] and function[x][y] are. But anyway let me consider it as an object declared somewhere like

SomeClass function;

(Because you said that it's operator overload, I think you won't be interested at array like SomeClass function[16][32];)

So function is an instance of type SomeClass. Then look up declaration of SomeClass for the return type of operator[] overload, just like

ReturnType operator[](ParamType);

Then function[x] will have the type ReturnType. Again look up ReturnType for the operator[] overload. If there is such a method, you could then use the expression function[x][y].

Note, unlike function(x, y), function[x][y] are 2 separate calls. So it's hard for compiler or runtime garantees the atomicity unless you use a lock in the context. A similar example is, libc says printf is atomic while successively calls to the overloaded operator<< in output stream are not. A statement like

std::cout << "hello" << std::endl;

might have problem in multi-thread application, but something like

printf("%s%s", "hello", "\n");

is fine.