How to create a template which gets input variables in square brackets?

Question

First of all, I know my question is too bizarre due to English is not my mother tongue.

I have used Google to learn this but I did not understand anything actually.

I want to create a function like this:

The function should take two parameters in square brackets and should get a parameter with assignment (=) operator.

I want to a function like this:

myFunction[Parameter1][Parameter2] = Parameter3;

Parameter1 and Parameter2 are integers. Parameter3 is a string.

And here is an example that describes what I want:

myFunction[3][5] = "stackoverflow";

How do I create that kind function?

Answer 1

You can do something like this:

#include <iostream>
#include <functional>

using FuncType=std::function<void(int, int, std::string)>;

class SubSubFunction {
public:
    SubSubFunction(FuncType func, int arg1, int arg2) : func_(func), arg1_(arg1), arg2_(arg2) {}
    SubSubFunction& operator =(std::string arg) {
        func_(arg1_, arg2_, arg);
        return *this;
    }
private:
    FuncType func_;
    int arg1_;
    int arg2_;
};

class SubFunction {
public:
    SubFunction(FuncType func, int arg1) : func_(func), arg1_(arg1) {}
    SubSubFunction operator [](int arg) {
        return {func_, arg1_, arg};
    }
private:
    FuncType func_;
    int arg1_;
};

class Function {
public:
    Function(FuncType func) : func_(func) {}
    SubFunction operator [](int arg) {
        return {func_, arg};
    }
private:
    FuncType func_;
};

int main()
{
    Function myFunction([](int arg1, int arg2, std::string arg3){
        std::cout << "Arg1: " << arg1 << ", arg2: " << arg2 << ", arg3: " << arg3 << std::endl;
    });
    myFunction[3][5] = "stackoverflow";
}