// Components for manipulating non-owning sequences of characters -*- C++ -*- // Copyright (C) 2013-2020 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. // Under Section 7 of GPL version 3, you are granted additional // permissions described in the GCC Runtime Library Exception, version // 3.1, as published by the Free Software Foundation. // You should have received a copy of the GNU General Public License and // a copy of the GCC Runtime Library Exception along with this program; // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see // <http://www.gnu.org/licenses/>. /** @file experimental/string_view * This is a TS C++ Library header. * @ingroup libfund-ts */ // // N3762 basic_string_view library // #ifndef _GLIBCXX_EXPERIMENTAL_STRING_VIEW #define _GLIBCXX_EXPERIMENTAL_STRING_VIEW 1 #pragma GCC system_header #if __cplusplus >= 201402L #include <string> #include <limits> #include <experimental/bits/lfts_config.h> namespace std _GLIBCXX_VISIBILITY(default) { _GLIBCXX_BEGIN_NAMESPACE_VERSION namespace experimental { inline namespace fundamentals_v1 { #define __cpp_lib_experimental_string_view 201411 /** * @class basic_string_view <experimental/string_view> * @brief A non-owning reference to a string. * * @ingroup strings * @ingroup sequences * @ingroup libfund-ts * * @tparam _CharT Type of character * @tparam _Traits Traits for character type, defaults to * char_traits<_CharT>. * * A basic_string_view looks like this: * * @code * _CharT* _M_str * size_t _M_len * @endcode */ template<typename _CharT, typename _Traits = std::char_traits<_CharT>> class basic_string_view { public: // types using traits_type = _Traits; using value_type = _CharT; using pointer = _CharT*; using const_pointer = const _CharT*; using reference = _CharT&; using const_reference = const _CharT&; using const_iterator = const _CharT*; using iterator = const_iterator; using const_reverse_iterator = std::reverse_iterator<const_iterator>; using reverse_iterator = const_reverse_iterator; using size_type = size_t; using difference_type = ptrdiff_t; static constexpr size_type npos = size_type(-1); // [string.view.cons], construct/copy constexpr basic_string_view() noexcept : _M_len{0}, _M_str{nullptr} { } constexpr basic_string_view(const basic_string_view&) noexcept = default; template<typename _Allocator> basic_string_view(const basic_string<_CharT, _Traits, _Allocator>& __str) noexcept : _M_len{__str.length()}, _M_str{__str.data()} { } constexpr basic_string_view(const _CharT* __str) : _M_len{__str == nullptr ? 0 : traits_type::length(__str)}, _M_str{__str} { } constexpr basic_string_view(const _CharT* __str, size_type __len) : _M_len{__len}, _M_str{__str} { } basic_string_view& operator=(const basic_string_view&) noexcept = default; // [string.view.iterators], iterators constexpr const_iterator begin() const noexcept { return this->_M_str; } constexpr const_iterator end() const noexcept { return this->_M_str + this->_M_len; } constexpr const_iterator cbegin() const noexcept { return this->_M_str; } constexpr const_iterator cend() const noexcept { return this->_M_str + this->_M_len; } const_reverse_iterator rbegin() const noexcept { return const_reverse_iterator(this->end()); } const_reverse_iterator rend() const noexcept { return const_reverse_iterator(this->begin()); } const_reverse_iterator crbegin() const noexcept { return const_reverse_iterator(this->end()); } const_reverse_iterator crend() const noexcept { return const_reverse_iterator(this->begin()); } // [string.view.capacity], capacity constexpr size_type size() const noexcept { return this->_M_len; } constexpr size_type length() const noexcept { return _M_len; } constexpr size_type max_size() const noexcept { return (npos - sizeof(size_type) - sizeof(void*)) / sizeof(value_type) / 4; } _GLIBCXX_NODISCARD constexpr bool empty() const noexcept { return this->_M_len == 0; } // [string.view.access], element access constexpr const _CharT& operator[](size_type __pos) const { __glibcxx_assert(__pos < this->_M_len); return *(this->_M_str + __pos); } constexpr const _CharT& at(size_type __pos) const { return __pos < this->_M_len ? *(this->_M_str + __pos) : (__throw_out_of_range_fmt(__N("basic_string_view::at: __pos " "(which is %zu) >= this->size() " "(which is %zu)"), __pos, this->size()), *this->_M_str); } constexpr const _CharT& front() const { __glibcxx_assert(this->_M_len > 0); return *this->_M_str; } constexpr const _CharT& back() const { __glibcxx_assert(this->_M_len > 0); return *(this->_M_str + this->_M_len - 1); } constexpr const _CharT* data() const noexcept { return this->_M_str; } // [string.view.modifiers], modifiers: constexpr void remove_prefix(size_type __n) { __glibcxx_assert(this->_M_len >= __n); this->_M_str += __n; this->_M_len -= __n; } constexpr void remove_suffix(size_type __n) { this->_M_len -= __n; } constexpr void swap(basic_string_view& __sv) noexcept { auto __tmp = *this; *this = __sv; __sv = __tmp; } // [string.view.ops], string operations: template<typename _Allocator> explicit operator basic_string<_CharT, _Traits, _Allocator>() const { return { this->_M_str, this->_M_len }; } template<typename _Allocator = std::allocator<_CharT>> basic_string<_CharT, _Traits, _Allocator> to_string(const _Allocator& __alloc = _Allocator()) const { return { this->_M_str, this->_M_len, __alloc }; } size_type copy(_CharT* __str, size_type __n, size_type __pos = 0) const { __glibcxx_requires_string_len(__str, __n); if (__pos > this->_M_len) __throw_out_of_range_fmt(__N("basic_string_view::copy: __pos " "(which is %zu) > this->size() " "(which is %zu)"), __pos, this->size()); size_type __rlen{std::min(__n, size_type{this->_M_len - __pos})}; for (auto __begin = this->_M_str + __pos, __end = __begin + __rlen; __begin != __end;) *__str++ = *__begin++; return __rlen; } // [string.view.ops], string operations: constexpr basic_string_view substr(size_type __pos = 0, size_type __n = npos) const { return __pos <= this->_M_len ? basic_string_view{this->_M_str + __pos, std::min(__n, size_type{this->_M_len - __pos})} : (__throw_out_of_range_fmt(__N("basic_string_view::substr: __pos " "(which is %zu) > this->size() " "(which is %zu)"), __pos, this->size()), basic_string_view{}); } constexpr int compare(basic_string_view __str) const noexcept { int __ret = traits_type::compare(this->_M_str, __str._M_str, std::min(this->_M_len, __str._M_len)); if (__ret == 0) __ret = _S_compare(this->_M_len, __str._M_len); return __ret; } constexpr int compare(size_type __pos1, size_type __n1, basic_string_view __str) const { return this->substr(__pos1, __n1).compare(__str); } constexpr int compare(size_type __pos1, size_type __n1, basic_string_view __str, size_type __pos2, size_type __n2) const { return this->substr(__pos1, __n1).compare(__str.substr(__pos2, __n2)); } constexpr int compare(const _CharT* __str) const noexcept { return this->compare(basic_string_view{__str}); } constexpr int compare(size_type __pos1, size_type __n1, const _CharT* __str) const { return this->substr(__pos1, __n1).compare(basic_string_view{__str}); } constexpr int compare(size_type __pos1, size_type __n1, const _CharT* __str, size_type __n2) const { return this->substr(__pos1, __n1) .compare(basic_string_view(__str, __n2)); } constexpr size_type find(basic_string_view __str, size_type __pos = 0) const noexcept { return this->find(__str._M_str, __pos, __str._M_len); } constexpr size_type find(_CharT __c, size_type __pos=0) const noexcept; constexpr size_type find(const _CharT* __str, size_type __pos, size_type __n) const noexcept; constexpr size_type find(const _CharT* __str, size_type __pos=0) const noexcept { return this->find(__str, __pos, traits_type::length(__str)); } constexpr size_type rfind(basic_string_view __str, size_type __pos = npos) const noexcept { return this->rfind(__str._M_str, __pos, __str._M_len); } constexpr size_type rfind(_CharT __c, size_type __pos = npos) const noexcept; constexpr size_type rfind(const _CharT* __str, size_type __pos, size_type __n) const noexcept; constexpr size_type rfind(const _CharT* __str, size_type __pos = npos) const noexcept { return this->rfind(__str, __pos, traits_type::length(__str)); } constexpr size_type find_first_of(basic_string_view __str, size_type __pos = 0) const noexcept { return this->find_first_of(__str._M_str, __pos, __str._M_len); } constexpr size_type find_first_of(_CharT __c, size_type __pos = 0) const noexcept { return this->find(__c, __pos); } constexpr size_type find_first_of(const _CharT* __str, size_type __pos, size_type __n) const; constexpr size_type find_first_of(const _CharT* __str, size_type __pos = 0) const noexcept { return this->find_first_of(__str, __pos, traits_type::length(__str)); } constexpr size_type find_last_of(basic_string_view __str, size_type __pos = npos) const noexcept { return this->find_last_of(__str._M_str, __pos, __str._M_len); } constexpr size_type find_last_of(_CharT __c, size_type __pos=npos) const noexcept { return this->rfind(__c, __pos); } constexpr size_type find_last_of(const _CharT* __str, size_type __pos, size_type __n) const; constexpr size_type find_last_of(const _CharT* __str, size_type __pos = npos) const noexcept { return this->find_last_of(__str, __pos, traits_type::length(__str)); } constexpr size_type find_first_not_of(basic_string_view __str, size_type __pos = 0) const noexcept { return this->find_first_not_of(__str._M_str, __pos, __str._M_len); } constexpr size_type find_first_not_of(_CharT __c, size_type __pos = 0) const noexcept; constexpr size_type find_first_not_of(const _CharT* __str, size_type __pos, size_type __n) const; constexpr size_type find_first_not_of(const _CharT* __str, size_type __pos = 0) const noexcept { return this->find_first_not_of(__str, __pos, traits_type::length(__str)); } constexpr size_type find_last_not_of(basic_string_view __str, size_type __pos = npos) const noexcept { return this->find_last_not_of(__str._M_str, __pos, __str._M_len); } constexpr size_type find_last_not_of(_CharT __c, size_type __pos = npos) const noexcept; constexpr size_type find_last_not_of(const _CharT* __str, size_type __pos, size_type __n) const; constexpr size_type find_last_not_of(const _CharT* __str, size_type __pos = npos) const noexcept { return this->find_last_not_of(__str, __pos, traits_type::length(__str)); } private: static constexpr int _S_compare(size_type __n1, size_type __n2) noexcept { return difference_type(__n1 - __n2) > std::numeric_limits<int>::max() ? std::numeric_limits<int>::max() : difference_type(__n1 - __n2) < std::numeric_limits<int>::min() ? std::numeric_limits<int>::min() : static_cast<int>(difference_type(__n1 - __n2)); } size_t _M_len; const _CharT* _M_str; }; // [string.view.comparison], non-member basic_string_view comparison functions // Several of these functions use type_identity_t to create a non-deduced // context, so that only one argument participates in template argument // deduction and the other argument gets implicitly converted to the deduced // type (see N3766). template<typename _CharT, typename _Traits> constexpr bool operator==(basic_string_view<_CharT, _Traits> __x, basic_string_view<_CharT, _Traits> __y) noexcept { return __x.size() == __y.size() && __x.compare(__y) == 0; } template<typename _CharT, typename _Traits> constexpr bool operator==(basic_string_view<_CharT, _Traits> __x, __type_identity_t<basic_string_view<_CharT, _Traits>> __y) noexcept { return __x.size() == __y.size() && __x.compare(__y) == 0; } template<typename _CharT, typename _Traits> constexpr bool operator==(__type_identity_t<basic_string_view<_CharT, _Traits>> __x, basic_string_view<_CharT, _Traits> __y) noexcept { return __x.size() == __y.size() && __x.compare(__y) == 0; } template<typename _CharT, typename _Traits> constexpr bool operator!=(basic_string_view<_CharT, _Traits> __x, basic_string_view<_CharT, _Traits> __y) noexcept { return !(__x == __y); } template<typename _CharT, typename _Traits> constexpr bool operator!=(basic_string_view<_CharT, _Traits> __x, __type_identity_t<basic_string_view<_CharT, _Traits>> __y) noexcept { return !(__x == __y); } template<typename _CharT, typename _Traits> constexpr bool operator!=(__type_identity_t<basic_string_view<_CharT, _Traits>> __x, basic_string_view<_CharT, _Traits> __y) noexcept { return !(__x == __y); } template<typename _CharT, typename _Traits> constexpr bool operator< (basic_string_view<_CharT, _Traits> __x, basic_string_view<_CharT, _Traits> __y) noexcept { return __x.compare(__y) < 0; } template<typename _CharT, typename _Traits> constexpr bool operator< (basic_string_view<_CharT, _Traits> __x, __type_identity_t<basic_string_view<_CharT, _Traits>> __y) noexcept { return __x.compare(__y) < 0; } template<typename _CharT, typename _Traits> constexpr bool operator< (__type_identity_t<basic_string_view<_CharT, _Traits>> __x, basic_string_view<_CharT, _Traits> __y) noexcept { return __x.compare(__y) < 0; } template<typename _CharT, typename _Traits> constexpr bool operator> (basic_string_view<_CharT, _Traits> __x, basic_string_view<_CharT, _Traits> __y) noexcept { return __x.compare(__y) > 0; } template<typename _CharT, typename _Traits> constexpr bool operator> (basic_string_view<_CharT, _Traits> __x, __type_identity_t<basic_string_view<_CharT, _Traits>> __y) noexcept { return __x.compare(__y) > 0; } template<typename _CharT, typename _Traits> constexpr bool operator> (__type_identity_t<basic_string_view<_CharT, _Traits>> __x, basic_string_view<_CharT, _Traits> __y) noexcept { return __x.compare(__y) > 0; } template<typename _CharT, typename _Traits> constexpr bool operator<=(basic_string_view<_CharT, _Traits> __x, basic_string_view<_CharT, _Traits> __y) noexcept { return __x.compare(__y) <= 0; } template<typename _CharT, typename _Traits> constexpr bool operator<=(basic_string_view<_CharT, _Traits> __x, __type_identity_t<basic_string_view<_CharT, _Traits>> __y) noexcept { return __x.compare(__y) <= 0; } template<typename _CharT, typename _Traits> constexpr bool operator<=(__type_identity_t<basic_string_view<_CharT, _Traits>> __x, basic_string_view<_CharT, _Traits> __y) noexcept { return __x.compare(__y) <= 0; } template<typename _CharT, typename _Traits> constexpr bool operator>=(basic_string_view<_CharT, _Traits> __x, basic_string_view<_CharT, _Traits> __y) noexcept { return __x.compare(__y) >= 0; } template<typename _CharT, typename _Traits> constexpr bool operator>=(basic_string_view<_CharT, _Traits> __x, __type_identity_t<basic_string_view<_CharT, _Traits>> __y) noexcept { return __x.compare(__y) >= 0; } template<typename _CharT, typename _Traits> constexpr bool operator>=(__type_identity_t<basic_string_view<_CharT, _Traits>> __x, basic_string_view<_CharT, _Traits> __y) noexcept { return __x.compare(__y) >= 0; } // [string.view.io], Inserters and extractors template<typename _CharT, typename _Traits> inline basic_ostream<_CharT, _Traits>& operator<<(basic_ostream<_CharT, _Traits>& __os, basic_string_view<_CharT,_Traits> __str) { return __ostream_insert(__os, __str.data(), __str.size()); } // basic_string_view typedef names using string_view = basic_string_view<char>; #ifdef _GLIBCXX_USE_WCHAR_T using wstring_view = basic_string_view<wchar_t>; #endif #ifdef _GLIBCXX_USE_CHAR8_T using u8string_view = basic_string_view<char8_t>; #endif using u16string_view = basic_string_view<char16_t>; using u32string_view = basic_string_view<char32_t>; } // namespace fundamentals_v1 } // namespace experimental // [string.view.hash], hash support: template<typename _Tp> struct hash; template<> struct hash<experimental::string_view> : public __hash_base<size_t, experimental::string_view> { size_t operator()(const experimental::string_view& __str) const noexcept { return std::_Hash_impl::hash(__str.data(), __str.length()); } }; template<> struct __is_fast_hash<hash<experimental::string_view>> : std::false_type { }; #ifdef _GLIBCXX_USE_WCHAR_T template<> struct hash<experimental::wstring_view> : public __hash_base<size_t, wstring> { size_t operator()(const experimental::wstring_view& __s) const noexcept { return std::_Hash_impl::hash(__s.data(), __s.length() * sizeof(wchar_t)); } }; template<> struct __is_fast_hash<hash<experimental::wstring_view>> : std::false_type { }; #endif #ifdef _GLIBCXX_USE_CHAR8_T template<> struct hash<experimental::u8string_view> : public __hash_base<size_t, experimental::u8string_view> { size_t operator()(const experimental::u8string_view& __s) const noexcept { return std::_Hash_impl::hash(__s.data(), __s.length()); } }; template<> struct __is_fast_hash<hash<experimental::u8string_view>> : std::false_type { }; #endif template<> struct hash<experimental::u16string_view> : public __hash_base<size_t, experimental::u16string_view> { size_t operator()(const experimental::u16string_view& __s) const noexcept { return std::_Hash_impl::hash(__s.data(), __s.length() * sizeof(char16_t)); } }; template<> struct __is_fast_hash<hash<experimental::u16string_view>> : std::false_type { }; template<> struct hash<experimental::u32string_view> : public __hash_base<size_t, experimental::u32string_view> { size_t operator()(const experimental::u32string_view& __s) const noexcept { return std::_Hash_impl::hash(__s.data(), __s.length() * sizeof(char32_t)); } }; template<> struct __is_fast_hash<hash<experimental::u32string_view>> : std::false_type { }; namespace experimental { // I added these EMSR. inline namespace literals { inline namespace string_view_literals { #pragma GCC diagnostic push #pragma GCC diagnostic ignored "-Wliteral-suffix" inline constexpr basic_string_view<char> operator""sv(const char* __str, size_t __len) noexcept { return basic_string_view<char>{__str, __len}; } #ifdef _GLIBCXX_USE_WCHAR_T inline constexpr basic_string_view<wchar_t> operator""sv(const wchar_t* __str, size_t __len) noexcept { return basic_string_view<wchar_t>{__str, __len}; } #endif #ifdef _GLIBCXX_USE_CHAR8_T inline constexpr basic_string_view<char8_t> operator""sv(const char8_t* __str, size_t __len) noexcept { return basic_string_view<char8_t>{__str, __len}; } #endif inline constexpr basic_string_view<char16_t> operator""sv(const char16_t* __str, size_t __len) noexcept { return basic_string_view<char16_t>{__str, __len}; } inline constexpr basic_string_view<char32_t> operator""sv(const char32_t* __str, size_t __len) noexcept { return basic_string_view<char32_t>{__str, __len}; } #pragma GCC diagnostic pop } // namespace string_literals } // namespace literals } // namespace experimental #if __cpp_lib_concepts namespace ranges { // Opt-in to borrowed_range concept template<typename _CharT, typename _Traits> inline constexpr bool enable_borrowed_range<experimental::basic_string_view<_CharT, _Traits>> = true; // Opt-in to view concept template<typename _CharT, typename _Traits> inline constexpr bool enable_view<experimental::basic_string_view<_CharT, _Traits>> = true; } #endif _GLIBCXX_END_NAMESPACE_VERSION } // namespace std #include <experimental/bits/string_view.tcc> #endif // __cplusplus <= 201103L #endif // _GLIBCXX_EXPERIMENTAL_STRING_VIEW