C++ Tuples

The test class

  1: class MYObj
  2: {
  3: 	public:
  4: 		MYObj(std::string pName);
  5: 	public:
  6: 		std::string mName;
  7: };
  8: 
  9: MYObj::MYObj(std::string pName)
 10: {
 11: 	mName = pName;
 12: }

An example for simple C++ tuple:

  1: 	MYObj myObj;
  2: 	//Create a tuple with 3 different variable types 
  3: 	auto myTuple = std::make_tuple ("Zvika" , 42 , myObj );
  4: 	//Get the first member of the tuple 
  5: 	auto myName = std::get<0>(myTuple);
  6: 	std::cout << myName; 

Use of forward_as_tuple in order to insert to the tuple right values

  1: 	MYObj myObj ("Lion");
  2: 	//Create a tuple with 3 different variable types 
  3: 	auto myTuple = std::make_tuple ("Cat" , 42 , myObj );
  4: 	//Create a tuple with 3 different variable types of right values 
  5: 	auto myTupleAsRightValue = std::forward_as_tuple ("cat" , 42 , myObj );
  6: 	//Chaneg the object state 
  7: 	myObj.mName = "weasel";
  8:    //Get the 3 member of the tuple 
  9: 	auto myName = std::get<2>(myTuple);
 10: 	
 11: 	std::cout << myName.mName <<"\r\n";
 12: 	//Get the 3 member of the tuple of right values 	
 13: 	auto myNameAsRightValue = std::get<2>(myTupleAsRightValue);
 14: 	
 15: 	std::cout << myNameAsRightValue.mName  <<"\r\n";

The result:
Lion
weasel

Declare the tuple without the auto keyword

  1: MYObj myObj ("Lion");
  2: 	//Create a tuple with 3 different variable types 
  3: 	std::tuple <std::string , int , MYObj> myTuple = std::make_tuple ("Cat" , 42 , myObj );
  4: 	//Create a tuple with 3 different variable types of right values 
  5: 	int theVal = 42;
  6: 	std::string theStr = "cat";
  7: 
  8: 	std::tuple <std::string &, int &, MYObj &> myTupleAsRightValue = std::forward_as_tuple (theStr , theVal  , myObj );
  9: 

Reference to Tuple:
http://en.cppreference.com/w/cpp/utility/tuple/forward_as_tuple