libcxx/test/std/iterators/iterator.primitives/iterator.traits/pointer.pass.cpp

   1 //===----------------------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 // <iterator>
  10
  11 // template<class T>
  12 // struct iterator_traits<T*>
  13 // {
  14 //   typedef ptrdiff_t                  difference_type;
  15 //   typedef T                          value_type;
  16 //   typedef T*                         pointer;
  17 //   typedef T&                         reference;
  18 //   typedef random_access_iterator_tag iterator_category;
  19 //   typedef contiguous_iterator_tag iterator_category; // C++20
  20 // };
  21
  22 #include <iterator>
  23 #include <cstddef>
  24 #include <type_traits>
  25
  26 #include "test_macros.h"
  27
  28 struct A {};
  29
  30 int main(int, char**)
  31 {
  32     typedef std::iterator_traits<A*> It;
  33     static_assert((std::is_same<It::difference_type, std::ptrdiff_t>::value), "");
  34     static_assert((std::is_same<It::value_type, A>::value), "");
  35     static_assert((std::is_same<It::pointer, A*>::value), "");
  36     static_assert((std::is_same<It::reference, A&>::value), "");
  37     static_assert((std::is_same<It::iterator_category, std::random_access_iterator_tag>::value), "");
  38 #if TEST_STD_VER > 17
  39     ASSERT_SAME_TYPE(It::iterator_concept, std::contiguous_iterator_tag);
  40 #endif
  41   return 0;
  42 }