Constructor arguments from tuple

Question

Suppose I have a template which is parametrized by a class type and a number of argument types. a set of arguments matching these types are stored in a tuple. How can one pa

Answer 1

C++17 has std::make_from_tuple for this:

template 
struct foo
{
  std::tuple args;
  T gen() { return std::make_from_tuple(args); }
};