Element-wise tuple addition

Question

I have some values held in a tuple, and I am looking to add another tuple to it element-wise. So I would like functionality like this:

std::tuple         


        

Answer 1

Here is an operator definition for syntax #1:

template  std::tuple operator + (const std::tuple& lhs, const std::tuple& rhs)
{
   return std::make_tuple(std::get<0>(lhs) + std::get<0>(rhs), std::get<1>(lhs) + std::get<1>(rhs));
}

Syntax #2 and #3 are not possible without creating a custom struct, because they can only be defined as members of the classes they operate on (and you can't touch existing classes in namespace std).