mrkkrj

#include <utility>

// left fold by hand
template <typename F,typename Acc, typename... T>
  constexpr auto foldLeft_initial(F func, Acc acc, T... xs)
{
    auto step = [=](auto self, auto acc_, auto x_, auto... xs_) 
    {        
            auto sum = func(acc_, x_);

mrkkrj

#include <iostream>

template<typename Lhs, typename Rhs>
struct assignment_t
{
  using lhs_t = Lhs;
  using rhs_t = Rhs;
  lhs_t _lhs;
  rhs_t _rhs;   
};