Line data    Source code

       1            0 : // Distributed under the MIT License.
       2              : // See LICENSE.txt for details.
       3              : 
       4              : #pragma once
       5              : 
       6              : #include <type_traits>
       7              : 
       8              : #include "Utilities/TMPL.hpp"
       9              : 
      10            0 : namespace Options::protocols {
      11              : /*!
      12              :  * \brief Compile-time information for factory-creation
      13              :  *
      14              :  * A class conforming to this protocol is placed in the metavariables
      15              :  * to provide information on the set of derived classes for each
      16              :  * factory-creatable base class.  The conforming class must provide
      17              :  * the following type aliases:
      18              :  *
      19              :  * - `factory_classes`: A `tmpl::map` from the base class to the list
      20              :  *   of derived classes. List all derived classes that should be
      21              :  *   factory-creatable, e.g. through input-file options.
      22              :  *
      23              :  * Here's an example for a class conforming to this protocol:
      24              :  *
      25              :  * \snippet Options/Test_Factory.cpp factory_creation
      26              :  */
      27            1 : struct FactoryCreation {
      28              :   template <typename ConformingType>
      29            0 :   struct test {
      30            0 :     using factory_classes = typename ConformingType::factory_classes;
      31              : 
      32              :     template <typename BaseClass, typename DerivedClass>
      33            0 :     struct factory_class_is_derived_from_base_class : std::true_type {
      34              :       static_assert(std::is_base_of_v<BaseClass, DerivedClass>,
      35              :                     "FactoryCreation protocol: The first template argument to "
      36              :                     "this struct is not a base class of the second.");
      37              :     };
      38              : 
      39            0 :     using all_classes_are_derived_classes = tmpl::all<
      40              :         factory_classes,
      41              :         tmpl::bind<
      42              :             tmpl::all, tmpl::bind<tmpl::back, tmpl::_1>,
      43              :             tmpl::defer<factory_class_is_derived_from_base_class<
      44              :                 tmpl::bind<tmpl::front, tmpl::parent<tmpl::_1>>, tmpl::_1>>>>;
      45              : 
      46              :     static_assert(all_classes_are_derived_classes::value);
      47              :   };
      48              : };
      49              : }  // namespace Options::protocols