| // Copyright (C) 2017-2020 Free Software Foundation, Inc. |
| // |
| // This file is part of the GNU ISO C++ Library. This library is free |
| // software; you can redistribute it and/or modify it under the |
| // terms of the GNU General Public License as published by the |
| // Free Software Foundation; either version 3, or (at your option) |
| // any later version. |
| |
| // This library is distributed in the hope that it will be useful, |
| // but WITHOUT ANY WARRANTY; without even the implied warranty of |
| // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| // GNU General Public License for more details. |
| |
| // You should have received a copy of the GNU General Public License along |
| // with this library; see the file COPYING3. If not see |
| // <http://www.gnu.org/licenses/>. |
| |
| // { dg-options "-std=gnu++17" } |
| // { dg-do compile { target c++17 } } |
| |
| #include <string_view> |
| |
| struct constexpr_char_traits : std::char_traits<char> |
| { |
| static constexpr size_t |
| length(const char* val) |
| { |
| size_t res = 0; |
| for (; val[res] != '\0'; ++res) |
| ; |
| return res; |
| } |
| |
| static constexpr int |
| compare(const char* lhs, const char* rhs, std::size_t count) |
| { |
| for (size_t pos = 0; pos < count; ++pos) |
| { |
| if (lhs[pos] != rhs[pos]) |
| return lhs[pos] - rhs[pos]; |
| } |
| return 0; |
| } |
| }; |
| |
| using string_view = std::basic_string_view<char, constexpr_char_traits>; |
| |
| constexpr |
| string_view get() |
| { |
| string_view res = "x::"; |
| string_view start_pattern = "x"; |
| res = res.substr(res.find(start_pattern) + start_pattern.size()); |
| res = res.substr(0, res.find_first_of(";]")); |
| res = res.substr(res.rfind("::")); |
| return res; |
| } |
| |
| static_assert( get() == get() ); |
| |
| using std::u16string_view; |
| |
| constexpr |
| u16string_view get16() |
| { |
| u16string_view res = u"x::"; |
| u16string_view start_pattern = u"x"; |
| res = res.substr(res.find(start_pattern) + start_pattern.size()); |
| res = res.substr(0, res.find_first_of(u";]")); |
| res = res.substr(res.rfind(u"::")); |
| return res; |
| } |
| |
| static_assert( get16() == get16() ); |
| |
| using std::u32string_view; |
| |
| constexpr |
| u32string_view get32() |
| { |
| u32string_view res = U"x::"; |
| u32string_view start_pattern = U"x"; |
| res = res.substr(res.find(start_pattern) + start_pattern.size()); |
| res = res.substr(0, res.find_first_of(U";]")); |
| res = res.substr(res.rfind(U"::")); |
| return res; |
| } |
| |
| static_assert( get32() == get32() ); |