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// <iterator> 11 12// template<class Iter> 13// struct iterator_traits 14// { 15// typedef typename Iter::difference_type difference_type; 16// typedef typename Iter::value_type value_type; 17// typedef typename Iter::pointer pointer; 18// typedef typename Iter::reference reference; 19// typedef typename Iter::iterator_category iterator_category; 20// }; 21 22#include <iterator> 23#include <type_traits> 24 25struct A {}; 26 27struct test_iterator 28{ 29 typedef int difference_type; 30 typedef A value_type; 31 typedef A* pointer; 32 typedef A& reference; 33 typedef std::forward_iterator_tag iterator_category; 34}; 35 36int main() 37{ 38 typedef std::iterator_traits<test_iterator> It; 39 static_assert((std::is_same<It::difference_type, int>::value), ""); 40 static_assert((std::is_same<It::value_type, A>::value), ""); 41 static_assert((std::is_same<It::pointer, A*>::value), ""); 42 static_assert((std::is_same<It::iterator_category, std::forward_iterator_tag>::value), ""); 43} 44