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
11 // <string_view>
12
13 // void remove_prefix(size_type _n)
14
15 #include <experimental/string_view>
16 #include <cassert>
17 #include <iostream>
18
19 template<typename CharT>
test(const CharT * s,size_t len)20 void test ( const CharT *s, size_t len ) {
21 typedef std::experimental::basic_string_view<CharT> SV;
22 {
23 SV sv1 ( s );
24 assert ( sv1.size() == len );
25 assert ( sv1.data() == s );
26
27 if ( len > 0 ) {
28 sv1.remove_prefix ( 1 );
29 assert ( sv1.size() == (len - 1));
30 assert ( sv1.data() == (s + 1));
31 sv1.remove_prefix ( len - 1 );
32 }
33
34 assert ( sv1.size() == 0 );
35 sv1.remove_prefix ( 0 );
36 assert ( sv1.size() == 0 );
37 }
38 }
39
40 #if _LIBCPP_STD_VER > 11
test_ce(size_t n,size_t k)41 constexpr size_t test_ce ( size_t n, size_t k ) {
42 typedef std::experimental::basic_string_view<char> SV;
43 SV sv1{ "ABCDEFGHIJKL", n };
44 sv1.remove_prefix ( k );
45 return sv1.size();
46 }
47 #endif
48
main()49 int main () {
50 test ( "ABCDE", 5 );
51 test ( "a", 1 );
52 test ( "", 0 );
53
54 test ( L"ABCDE", 5 );
55 test ( L"a", 1 );
56 test ( L"", 0 );
57
58 #if __cplusplus >= 201103L
59 test ( u"ABCDE", 5 );
60 test ( u"a", 1 );
61 test ( u"", 0 );
62
63 test ( U"ABCDE", 5 );
64 test ( U"a", 1 );
65 test ( U"", 0 );
66 #endif
67
68 #if _LIBCPP_STD_VER > 11
69 {
70 static_assert ( test_ce ( 5, 0 ) == 5, "" );
71 static_assert ( test_ce ( 5, 1 ) == 4, "" );
72 static_assert ( test_ce ( 5, 5 ) == 0, "" );
73 static_assert ( test_ce ( 9, 3 ) == 6, "" );
74 }
75 #endif
76 }
77