libcxx/include/__iterator/back_insert_iterator.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___ITERATOR_BACK_INSERT_ITERATOR_H
  11 #define _LIBCPP___ITERATOR_BACK_INSERT_ITERATOR_H
  12
  13 #include <__config>
  14 #include <__cstddef/ptrdiff_t.h>
  15 #include <__iterator/iterator.h>
  16 #include <__iterator/iterator_traits.h>
  17 #include <__memory/addressof.h>
  18 #include <__utility/move.h>
  19
  20 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  21 #  pragma GCC system_header
  22 #endif
  23
  24 _LIBCPP_PUSH_MACROS
  25 #include <__undef_macros>
  26
  27 _LIBCPP_BEGIN_NAMESPACE_STD
  28
  29 _LIBCPP_SUPPRESS_DEPRECATED_PUSH
  30 template <class _Container>
  31 class _LIBCPP_TEMPLATE_VIS back_insert_iterator
  32 #if _LIBCPP_STD_VER <= 14 || !defined(_LIBCPP_ABI_NO_ITERATOR_BASES)
  33     : public iterator<output_iterator_tag, void, void, void, void>
  34 #endif
  35 {
  36   _LIBCPP_SUPPRESS_DEPRECATED_POP
  37
  38 protected:
  39   _Container* container;
  40
  41 public:
  42   typedef output_iterator_tag iterator_category;
  43   typedef void value_type;
  44 #if _LIBCPP_STD_VER >= 20
  45   typedef ptrdiff_t difference_type;
  46 #else
  47   typedef void difference_type;
  48 #endif
  49   typedef void pointer;
  50   typedef void reference;
  51   typedef _Container container_type;
  52
  53   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit back_insert_iterator(_Container& __x)
  54       : container(std::addressof(__x)) {}
  55   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 back_insert_iterator&
  56   operator=(const typename _Container::value_type& __value) {
  57     container->push_back(__value);
  58     return *this;
  59   }
  60 #ifndef _LIBCPP_CXX03_LANG
  61   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 back_insert_iterator&
  62   operator=(typename _Container::value_type&& __value) {
  63     container->push_back(std::move(__value));
  64     return *this;
  65   }
  66 #endif // _LIBCPP_CXX03_LANG
  67   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 back_insert_iterator& operator*() { return *this; }
  68   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 back_insert_iterator& operator++() { return *this; }
  69   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 back_insert_iterator operator++(int) { return *this; }
  70
  71   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Container* __get_container() const { return container; }
  72 };
  73 _LIBCPP_CTAD_SUPPORTED_FOR_TYPE(back_insert_iterator);
  74
  75 template <class _Container>
  76 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 back_insert_iterator<_Container>
  77 back_inserter(_Container& __x) {
  78   return back_insert_iterator<_Container>(__x);
  79 }
  80
  81 _LIBCPP_END_NAMESPACE_STD
  82
  83 _LIBCPP_POP_MACROS
  84
  85 #endif // _LIBCPP___ITERATOR_BACK_INSERT_ITERATOR_H