libcxx/include/__iterator/front_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_FRONT_INSERT_ITERATOR_H
  11 #define _LIBCPP___ITERATOR_FRONT_INSERT_ITERATOR_H
  12
  13 #include <__config>
  14 #include <__iterator/iterator.h>
  15 #include <__iterator/iterator_traits.h>
  16 #include <__memory/addressof.h>
  17 #include <__utility/move.h>
  18 #include <cstddef>
  19
  20 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  21 #pragma GCC system_header
  22 #endif
  23
  24 _LIBCPP_BEGIN_NAMESPACE_STD
  25
  26 _LIBCPP_SUPPRESS_DEPRECATED_PUSH
  27 template <class _Container>
  28 class _LIBCPP_TEMPLATE_VIS front_insert_iterator
  29 #if _LIBCPP_STD_VER <= 14 || !defined(_LIBCPP_ABI_NO_ITERATOR_BASES)
  30     : public iterator<output_iterator_tag, void, void, void, void>
  31 #endif
  32 {
  33 _LIBCPP_SUPPRESS_DEPRECATED_POP
  34 protected:
  35     _Container* container;
  36 public:
  37     typedef output_iterator_tag iterator_category;
  38     typedef void value_type;
  39 #if _LIBCPP_STD_VER > 17
  40     typedef ptrdiff_t difference_type;
  41 #else
  42     typedef void difference_type;
  43 #endif
  44     typedef void pointer;
  45     typedef void reference;
  46     typedef _Container container_type;
  47
  48     _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 explicit front_insert_iterator(_Container& __x) : container(_VSTD::addressof(__x)) {}
  49     _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 front_insert_iterator& operator=(const typename _Container::value_type& __value_)
  50         {container->push_front(__value_); return *this;}
  51 #ifndef _LIBCPP_CXX03_LANG
  52     _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 front_insert_iterator& operator=(typename _Container::value_type&& __value_)
  53         {container->push_front(_VSTD::move(__value_)); return *this;}
  54 #endif // _LIBCPP_CXX03_LANG
  55     _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 front_insert_iterator& operator*()     {return *this;}
  56     _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 front_insert_iterator& operator++()    {return *this;}
  57     _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 front_insert_iterator  operator++(int) {return *this;}
  58 };
  59
  60 template <class _Container>
  61 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
  62 front_insert_iterator<_Container>
  63 front_inserter(_Container& __x)
  64 {
  65     return front_insert_iterator<_Container>(__x);
  66 }
  67
  68 _LIBCPP_END_NAMESPACE_STD
  69
  70 #endif // _LIBCPP___ITERATOR_FRONT_INSERT_ITERATOR_H