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 // <string_view>
11 
12 // constexpr const_iterator end() const;
13 
14 #include <experimental/string_view>
15 #include <cassert>
16 
17 template <class S>
18 void
test(S s)19 test(S s)
20 {
21     const S& cs = s;
22     typename S::iterator e = s.end();
23     typename S::const_iterator ce1 = cs.end();
24     typename S::const_iterator ce2 = s.cend();
25 
26     if (s.empty())
27     {
28         assert(  e ==  s.begin());
29         assert(ce1 == cs.begin());
30         assert(ce2 ==  s.begin());
31     }
32     else
33     {
34         assert(  e !=  s.begin());
35         assert(ce1 != cs.begin());
36         assert(ce2 !=  s.begin());
37     }
38 
39     assert(  e -  s.begin() == s.size());
40     assert(ce1 - cs.begin() == cs.size());
41     assert(ce2 - s.cbegin() == s.size());
42 
43     assert(  e == ce1);
44     assert(  e == ce2);
45     assert(ce1 == ce2);
46 }
47 
48 
main()49 int main()
50 {
51     typedef std::experimental::string_view    string_view;
52     typedef std::experimental::u16string_view u16string_view;
53     typedef std::experimental::u32string_view u32string_view;
54     typedef std::experimental::wstring_view   wstring_view;
55 
56     test(string_view   ());
57     test(u16string_view());
58     test(u32string_view());
59     test(wstring_view  ());
60     test(string_view   ( "123"));
61     test(wstring_view  (L"123"));
62 #if __cplusplus >= 201103L
63     test(u16string_view{u"123"});
64     test(u32string_view{U"123"});
65 #endif
66 
67 #if _LIBCPP_STD_VER > 11
68     {
69     constexpr string_view       sv { "123", 3 };
70     constexpr u16string_view u16sv {u"123", 3 };
71     constexpr u32string_view u32sv {U"123", 3 };
72     constexpr wstring_view     wsv {L"123", 3 };
73 
74     static_assert (    sv.begin() !=    sv.end(), "" );
75     static_assert ( u16sv.begin() != u16sv.end(), "" );
76     static_assert ( u32sv.begin() != u32sv.end(), "" );
77     static_assert (   wsv.begin() !=   wsv.end(), "" );
78 
79     static_assert (    sv.begin() !=    sv.cend(), "" );
80     static_assert ( u16sv.begin() != u16sv.cend(), "" );
81     static_assert ( u32sv.begin() != u32sv.cend(), "" );
82     static_assert (   wsv.begin() !=   wsv.cend(), "" );
83     }
84 #endif
85 }
86