weighted_one_of_gen.cpp

template<typename Finalizer, typename Generator, typename... Generators>
auto weighted_one_of_gen(
   Finalizer finalizer, Weighted<Generator> head, Weighted<Generators>... tail)
{
   using Out = decltype(finalizer(head.m_value(std::declval<std::mt19937&>())));
   using OutGen = std::function<Out(std::mt19937&)>;

   auto map_first = [&](auto&& wg) -> Weighted<OutGen>
   {
      return Weighted<OutGen>{transform_gen(finalizer, wg.m_value), wg.m_weight};
   };

   std::vector<Weighted<OutGen>> weighted_gens{ map_first(head), map_first(tail)... };

   auto generator_picker = weighted_choice_gen(weighted_gens);
   return [=](std::mt19937& bit_gen)
   {
      return generator_picker(bit_gen)(bit_gen);
   };
}