Class lambda_visitor

include/simple/utils/visitors.hpp:60–72

    // It is an additional class to avoid diamond inheritance
    template<typename ReturnType, typename... Lambdas>
    struct lambda_visitor
    : boost::static_visitor<ReturnType>
    , lambda_visitor_helper<ReturnType, Lambdas...>
    {
      typedef lambda_visitor_helper<ReturnType, Lambdas...> Helper;

      lambda_visitor(Lambdas... lambdas)
      : Helper(lambdas...)
      {
      }

      using Helper::operator();
    };

    // Wrapper function to create a lambda_visitor instance.
    // This deduces the template arguments automatically, so you don't need to specify them.