Line data    Source code

       1           0 : // Distributed under the MIT License.
       2             : // See LICENSE.txt for details.
       3             : 
       4             : #pragma once
       5             : 
       6             : #include "Utilities/Requires.hpp"
       7             : #include "Utilities/TMPL.hpp"
       8             : #include "Utilities/TypeTraits/IsA.hpp"
       9             : 
      10             : /// \cond
      11             : namespace db {
      12             : struct PrefixTag;
      13             : struct SimpleTag;
      14             : }  // namespace db
      15             : 
      16             : namespace Tags {
      17             : template <typename TagsList>
      18             : struct Variables;
      19             : }  // namespace Tags
      20             : /// \endcond
      21             : 
      22             : namespace db {
      23             : 
      24             : /// \ingroup DataBoxTagsGroup
      25             : /// \brief Create a new `tmpl::list` of tags by wrapping each tag in `TagList`
      26             : /// in `Wrapper<_, Args...>`.
      27             : template <template <typename...> class Wrapper, typename TagList,
      28             :           typename... Args>
      29           1 : using wrap_tags_in =
      30             :     tmpl::transform<TagList, tmpl::bind<Wrapper, tmpl::_1, tmpl::pin<Args>...>>;
      31             : 
      32             : namespace detail {
      33             : template <template <typename...> class Prefix, typename Tag, typename... Args>
      34             : struct add_tag_prefix_impl {
      35             :   using type = Prefix<Tag, Args...>;
      36             : };
      37             : 
      38             : template <template <typename...> class Prefix, typename TagList,
      39             :           typename... Args>
      40             : struct add_tag_prefix_impl<Prefix, Tags::Variables<TagList>, Args...> {
      41             :   using type = Tags::Variables<wrap_tags_in<Prefix, TagList, Args...>>;
      42             : };
      43             : }  // namespace detail
      44             : 
      45             : /// \ingroup DataBoxTagsGroup
      46             : /// Wrap `Tag` in `Prefix<_, Args...>`, unless `Tag` is a Tags::Variables,
      47             : /// in which case this creates a new Tags::Variables, wrapping each tag in
      48             : /// `Tag::tags_list` with `Prefix<_, Args...>`.
      49             : template <template <typename...> class Prefix, typename Tag, typename... Args>
      50           1 : using add_tag_prefix =
      51             :     typename detail::add_tag_prefix_impl<Prefix, Tag, Args...>::type;
      52             : 
      53             : namespace detail {
      54             : template <typename>
      55             : struct remove_tag_prefix_impl;
      56             : 
      57             : template <typename WrappedTag, template <typename...> class Prefix,
      58             :           typename... Args>
      59             : struct remove_tag_prefix_impl<Prefix<WrappedTag, Args...>> {
      60             :   using type = WrappedTag;
      61             : };
      62             : 
      63             : template <typename TagList>
      64             : struct remove_tag_prefix_impl<Tags::Variables<TagList>> {
      65             :   using type = Tags::Variables<
      66             :       tmpl::transform<TagList, remove_tag_prefix_impl<tmpl::_1>>>;
      67             : };
      68             : }  // namespace detail
      69             : 
      70             : /// \ingroup DataBoxTagsGroup
      71             : /// Remove the outer prefix from a prefixed tag `Tag`, or remove the outer
      72             : /// prefix of each tag in `Tag::tags_list` if `Tag` is a Tags::Variables.
      73             : template <typename Tag>
      74           1 : using remove_tag_prefix = typename detail::remove_tag_prefix_impl<Tag>::type;
      75             : 
      76             : namespace detail {
      77             : 
      78             : template <typename Tag, typename = std::nullptr_t>
      79             : struct remove_all_prefixes_impl {
      80             :   using type = Tag;
      81             : };
      82             : 
      83             : template <typename Tag>
      84             : struct remove_all_prefixes_impl<
      85             :     Tag, Requires<std::is_base_of_v<db::PrefixTag, Tag>>> {
      86             :   using type = typename remove_all_prefixes_impl<typename Tag::tag>::type;
      87             : };
      88             : 
      89             : template <typename TagList>
      90             : struct remove_all_prefixes_impl<Tags::Variables<TagList>> {
      91             :   using type = Tags::Variables<
      92             :       tmpl::transform<TagList, remove_all_prefixes_impl<tmpl::_1>>>;
      93             : };
      94             : }  // namespace detail
      95             : 
      96             : /// \ingroup DataBoxTagsGroup
      97             : /// Completely remove all prefix tags from a Tag, or all prefixes from
      98             : /// the tags in `Tag::tags_list` if `Tag` is a Tags::Variables.
      99             : template <typename Tag>
     100           1 : using remove_all_prefixes =
     101             :     typename detail::remove_all_prefixes_impl<Tag>::type;
     102             : }  // namespace db