//********************************************************
// The following code example is taken from the book
//  C++ Move Semantics - The Complete Guide
//  by Nicolai M. Josuttis (www.josuttis.com)
//  http://www.cppmove.com
//
// The code is licensed under a
//  Creative Commons Attribution 4.0 International License
//  http://creativecommons.org/licenses/by/4.0/
//********************************************************


#include <iostream>
#include <string>
#include <vector>

template<typename T>
class Coll {
 private:
  std::vector<T> values;
 public:
  Coll() = default;

  // function in class template:
  void insert(T&& val) {
    values.push_back(std::move(val));
  }
};

int main()
{
  Coll<std::string> coll;
  //... 
  coll.insert(std::string{"prvalue"});  // OK
  std::string str{"lvalue"};
  coll.insert(str);              // ERROR: T&& of Coll<T> is not a universal reference
  coll.insert(std::move(str));   // OK
  //... 
}