libcxx/include/__memory/concepts.h

   1 // -*- C++ -*-
   2 //===----------------------------------------------------------------------===//
   3 //
   4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   5 // See https://llvm.org/LICENSE.txt for license information.
   6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #ifndef _LIBCPP___MEMORY_CONCEPTS_H
  11 #define _LIBCPP___MEMORY_CONCEPTS_H
  12
  13 #include <__config>
  14 #include <__iterator/concepts.h>
  15 #include <__iterator/iterator_traits.h>
  16 #include <__iterator/readable_traits.h>
  17 #include <__ranges/access.h>
  18 #include <__ranges/concepts.h>
  19 #include <concepts>
  20 #include <type_traits>
  21
  22 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  23 #pragma GCC system_header
  24 #endif
  25
  26 _LIBCPP_BEGIN_NAMESPACE_STD
  27
  28 #if !defined(_LIBCPP_HAS_NO_RANGES)
  29 namespace ranges {
  30
  31 // [special.mem.concepts]
  32
  33 // This concept ensures that uninitialized algorithms can construct an object
  34 // at the address pointed-to by the iterator, which requires an lvalue.
  35 template <class _Ip>
  36 concept __nothrow_input_iterator =
  37     input_iterator<_Ip> &&
  38     is_lvalue_reference_v<iter_reference_t<_Ip>> &&
  39     same_as<remove_cvref_t<iter_reference_t<_Ip>>, iter_value_t<_Ip>>;
  40
  41 template <class _Sp, class _Ip>
  42 concept __nothrow_sentinel_for = sentinel_for<_Sp, _Ip>;
  43
  44 template <class _Rp>
  45 concept __nothrow_input_range =
  46     range<_Rp> &&
  47     __nothrow_input_iterator<iterator_t<_Rp>> &&
  48     __nothrow_sentinel_for<sentinel_t<_Rp>, iterator_t<_Rp>>;
  49
  50 template <class _Ip>
  51 concept __nothrow_forward_iterator =
  52     __nothrow_input_iterator<_Ip> &&
  53     forward_iterator<_Ip> &&
  54     __nothrow_sentinel_for<_Ip, _Ip>;
  55
  56 template <class _Rp>
  57 concept __nothrow_forward_range =
  58     __nothrow_input_range<_Rp> &&
  59     __nothrow_forward_iterator<iterator_t<_Rp>>;
  60
  61 } // namespace ranges
  62 #endif // !defined(_LIBCPP_HAS_NO_RANGES)
  63
  64 _LIBCPP_END_NAMESPACE_STD
  65
  66 #endif // _LIBCPP___MEMORY_CONCEPTS_H