minus.pass.cpp (1418B)
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 // move_iterator 13 14 // template <RandomAccessIterator Iter1, RandomAccessIterator Iter2> 15 // requires HasMinus<Iter1, Iter2> 16 // auto 17 // operator-(const move_iterator<Iter1>& x, const move_iterator<Iter2>& y) 18 // -> decltype(x.base() - y.base()); 19 // 20 // constexpr in C++17 21 22 #include <iterator> 23 #include <cassert> 24 25 #include "test_macros.h" 26 #include "test_iterators.h" 27 28 template <class It> 29 void 30 test(It l, It r, typename std::iterator_traits<It>::difference_type x) 31 { 32 const std::move_iterator<It> r1(l); 33 const std::move_iterator<It> r2(r); 34 assert(r1 - r2 == x); 35 } 36 37 int main() 38 { 39 char s[] = "1234567890"; 40 test(random_access_iterator<char*>(s+5), random_access_iterator<char*>(s), 5); 41 test(s+5, s, 5); 42 43 #if TEST_STD_VER > 14 44 { 45 constexpr const char *p = "123456789"; 46 typedef std::move_iterator<const char *> MI; 47 constexpr MI it1 = std::make_move_iterator(p); 48 constexpr MI it2 = std::make_move_iterator(p+1); 49 static_assert( it1 - it2 == -1, ""); 50 static_assert( it2 - it1 == 1, ""); 51 } 52 #endif 53 }