1 //===----------------------------------------------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 #ifndef INPUT_ITERATOR_H 11 #define INPUT_ITERATOR_H 12 13 #include <iterator> 14 15 template <class It> 16 class input_iterator 17 { 18 It it_; 19 public: 20 typedef typename std::input_iterator_tag iterator_category; 21 typedef typename std::iterator_traits<It>::value_type value_type; 22 typedef typename std::iterator_traits<It>::difference_type difference_type; 23 typedef It pointer; 24 typedef typename std::iterator_traits<It>::reference reference; 25 input_iterator()26 input_iterator() : it_() {} input_iterator(It it)27 explicit input_iterator(It it) : it_(it) {} 28 29 reference operator*() const {return *it_;} 30 pointer operator->() const {return it_;} 31 32 input_iterator& operator++() {++it_; return *this;} 33 input_iterator operator++(int) {input_iterator tmp(*this); ++(*this); return tmp;} 34 35 friend bool operator==(const input_iterator& x, const input_iterator& y) 36 {return x.it_ == y.it_;} 37 friend bool operator!=(const input_iterator& x, const input_iterator& y) 38 {return !(x == y);} 39 }; 40 41 #endif // INPUT_ITERATOR_H 42