text: /// @copyright
  /// Copyright (C) 2020 Assured Information Security, Inc.
  ///
  /// @copyright
  /// Permission is hereby granted, free of charge, to any person obtaining a copy
  /// of this software and associated documentation files (the "Software"), to deal
  /// in the Software without restriction, including without limitation the rights
  /// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  /// copies of the Software, and to permit persons to whom the Software is
  /// furnished to do so, subject to the following conditions:
  ///
  /// @copyright
  /// The above copyright notice and this permission notice shall be included in
  /// all copies or substantial portions of the Software.
  ///
  /// @copyright
  /// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  /// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  /// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  /// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  /// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  /// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  /// SOFTWARE.
  ///
  /// @file is_detected.hpp
  ///
  
  #ifndef BSL_IS_DETECTED_HPP
  #define BSL_IS_DETECTED_HPP
  
  #include "detected.hpp"
  #include "is_convertible.hpp"
  #include "is_same.hpp"
  
  namespace bsl
  {
      /// @brief The alias template is_detected is equivalent to typename
      ///   detected_or<bsl::nonesuch, Op, Args...>::value_t.
      ///   It is an alias for bsl::true_type if the template-id Op<Args...>
      ///   denotes a valid type; otherwise it is an alias for bsl::false_type.
      template<template<class...> class Op, typename... Args>
      using is_detected = typename details::detector<nonesuch, void, Op, Args...>::value_t;
  
      /// @brief The alias template is_detected_exact checks whether
      ///   detected_t<Op, Args...> is Expected.
      template<class Expected, template<class...> class Op, class... Args>
      using is_detected_exact = is_same<Expected, detected_t<Op, Args...>>;
  
      /// @brief The alias template is_detected_convertible checks whether
      ///   detected_t<Op, Args...> is convertible to To.
      template<class To, template<class...> class Op, class... Args>
      using is_detected_convertible = is_convertible<detected_t<Op, Args...>, To>;
  }
  
  #endif
  