#include <iostream>
#include <functional>

//#include "analogmuxdemux.h"
using byte = unsigned char ;
typedef unsigned char byte ; // or a typedef

struct AnalogMux
{
    int AnalogRead( byte pin )
    {
        std::cout << "AnalogMux::AnalogRead: pin == " << int(pin) << '\n' ;
        // read
        return 0 ;
    }
};

class potentiometer
{
    // http://e...content-available-to-author-only...e.com/w/cpp/utility/functional/function
    using read_function_t = std::function< int(byte) >  ;
    //typedef std::function< int(byte) > read_function_t ; // alternate syntax

    byte pinNum;
    read_function_t readFunction ;

    public:
        potentiometer( byte, read_function_t fun );

        int analogRead(); // analogreads the pot
};

potentiometer::potentiometer( byte pin , read_function_t fun )
{
  pinNum = pin ;
  readFunction = fun ;
}

int potentiometer::analogRead()
{
  return readFunction(pinNum);
}

int non_member_AnalogRead( byte pin )
{
    std::cout << "non_member_AnalogRead: pin == " << int(pin) << '\n' ;
    // read
    return 0 ;
}

int main()
{
    AnalogMux aMux ; // instantiate a mux

    potentiometer p1( 1, non_member_AnalogRead ); // attached to pin 1
    p1.analogRead() ;

    // attached to input 4 on aMux
    // bind the function to AnalogMux::AnalogRead to be invoked on aMux
    // http://e...content-available-to-author-only...e.com/w/cpp/utility/functional/bind
    potentiometer p2( 4, std::bind( &AnalogMux::AnalogRead, aMux, std::placeholders::_1 ) ) ;
    p2.analogRead() ;
}