libcxx/test/std/strings/basic.string/input_iterator.h

   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 #ifndef INPUT_ITERATOR_H
  10 #define INPUT_ITERATOR_H
  11
  12 #include <iterator>
  13
  14 template <class It>
  15 class input_iterator
  16 {
  17     It it_;
  18 public:
  19     typedef typename std::input_iterator_tag                   iterator_category;
  20     typedef typename std::iterator_traits<It>::value_type      value_type;
  21     typedef typename std::iterator_traits<It>::difference_type difference_type;
  22     typedef It                                                 pointer;
  23     typedef typename std::iterator_traits<It>::reference       reference;
  24
  25     input_iterator() : it_() {}
  26     explicit input_iterator(It it) : it_(it) {}
  27
  28     reference operator*() const {return *it_;}
  29     pointer operator->() const {return it_;}
  30
  31     input_iterator& operator++() {++it_; return *this;}
  32     input_iterator operator++(int) {input_iterator tmp(*this); ++(*this); return tmp;}
  33
  34     friend bool operator==(const input_iterator& x, const input_iterator& y)
  35         {return x.it_ == y.it_;}
  36     friend bool operator!=(const input_iterator& x, const input_iterator& y)
  37         {return !(x == y);}
  38 };
  39
  40 #endif  // INPUT_ITERATOR_H