action_list_implementation.hpp

Go to the documentation of this file. Or view the newest version in sPHENIX GitHub for file action_list_implementation.hpp

// This file is part of the Acts project.
//
// Copyright (C) 2018 CERN for the benefit of the Acts project
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.

#pragma once

#include "Acts/Utilities/detail/MPL/type_collector.hpp"

#include <utility>

namespace Acts {
namespace detail {

namespace {

template <bool has_result = true>
struct action_caller {
  template <typename actor_t, typename result_t, typename propagator_state_t,
            typename stepper_t, typename navigator_t, typename... Args>
  static void action(const actor_t& act, propagator_state_t& state,
                     const stepper_t& stepper, const navigator_t& navigator,
                     result_t& result, Args&&... args) {
    act(state, stepper, navigator,
        result.template get<detail::result_type_t<actor_t>>(),
        std::forward<Args>(args)...);
  }
};

template <>
struct action_caller<false> {
  template <typename actor_t, typename result_t, typename propagator_state_t,
            typename stepper_t, typename navigator_t, typename... Args>
  static void action(const actor_t& act, propagator_state_t& state,
                     const stepper_t& stepper, const navigator_t& navigator,
                     result_t& /*result*/, Args&&... args) {
    act(state, stepper, navigator, std::forward<Args>(args)...);
  }
};
}  // end of anonymous namespace

template <typename... actors>
struct action_list_impl;

template <typename first, typename... others>
struct action_list_impl<first, others...> {
  template <typename T, typename propagator_state_t, typename stepper_t,
            typename navigator_t, typename result_t, typename... Args>
  static void action(const T& actors_tuple, propagator_state_t& state,
                     const stepper_t& stepper, const navigator_t& navigator,
                     result_t& result, Args&&... args) {
    constexpr bool has_result = has_result_type_v<first>;
    const auto& this_actor = std::get<first>(actors_tuple);
    action_caller<has_result>::action(this_actor, state, stepper, navigator,
                                      result, args...);
    action_list_impl<others...>::action(actors_tuple, state, stepper, navigator,
                                        result, args...);
  }
};

template <typename last>
struct action_list_impl<last> {
  template <typename T, typename propagator_state_t, typename stepper_t,
            typename navigator_t, typename result_t, typename... Args>
  static void action(const T& actors_tuple, propagator_state_t& state,
                     const stepper_t& stepper, const navigator_t& navigator,
                     result_t& result, Args&&... args) {
    constexpr bool has_result = has_result_type_v<last>;
    const auto& this_actor = std::get<last>(actors_tuple);
    action_caller<has_result>::action(this_actor, state, stepper, navigator,
                                      result, std::forward<Args>(args)...);
  }
};

template <>
struct action_list_impl<> {
  template <typename T, typename propagator_state_t, typename stepper_t,
            typename navigator_t, typename result_t, typename... Args>
  static void action(const T& /*actors_tuple*/, propagator_state_t& /*state*/,
                     const stepper_t& /*stepper*/,
                     const navigator_t& /*navigator*/, result_t& /*result*/,
                     Args&&... /*args*/) {}
};

}  // namespace detail
}  // namespace Acts