libcxx/test/std/iterators/predef.iterators/iterators.common/constraints.compile.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 // UNSUPPORTED: c++03, c++11, c++14, c++17
  10
  11 // template<input_or_output_iterator I, sentinel_for<I> S>
  12 //   requires (!same_as<I, S> && copyable<I>)
  13
  14 #include <iterator>
  15
  16 #include "test_iterators.h"
  17
  18 template<class I, class S>
  19 concept ValidCommonIterator = requires {
  20   typename std::common_iterator<I, S>;
  21 };
  22
  23 static_assert( ValidCommonIterator<int*, const int*>);
  24 static_assert(!ValidCommonIterator<int, int>); // !input_or_output_iterator<I>
  25 static_assert(!ValidCommonIterator<int*, float*>); // !sentinel_for<S, I>
  26 static_assert(!ValidCommonIterator<int*, int*>); // !same_as<I, S>
  27 static_assert(!ValidCommonIterator<cpp20_input_iterator<int*>, sentinel_wrapper<cpp20_input_iterator<int*>>>); // !copyable<I>