| /* |
| Copyright (c) Marshall Clow 2012-2015. |
| Copyright (c) Glen Joseph Fernandes 2019 (glenjofe@gmail.com) |
| |
| Distributed under the Boost Software License, Version 1.0. (See accompanying |
| file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
| |
| For more information, see http://www.boost.org |
| |
| Based on the StringRef implementation in LLVM (http://llvm.org) and |
| N3422 by Jeffrey Yasskin |
| http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3442.html |
| |
| */ |
| |
| #ifndef BOOST_STRING_REF_HPP |
| #define BOOST_STRING_REF_HPP |
| |
| #include <boost/config.hpp> |
| #include <boost/detail/workaround.hpp> |
| #include <boost/io/ostream_put.hpp> |
| #include <boost/utility/string_ref_fwd.hpp> |
| #include <boost/throw_exception.hpp> |
| |
| #include <cstddef> |
| #include <stdexcept> |
| #include <algorithm> |
| #include <iterator> |
| #include <string> |
| #include <iosfwd> |
| |
| #if defined(BOOST_NO_CXX11_DEFAULTED_FUNCTIONS) || (defined(BOOST_GCC) && ((BOOST_GCC+0) / 100) <= 406) |
| // GCC 4.6 cannot handle a defaulted function with noexcept specifier |
| #define BOOST_STRING_REF_NO_CXX11_DEFAULTED_NOEXCEPT_FUNCTIONS |
| #endif |
| |
| namespace boost { |
| |
| namespace detail { |
| // A helper functor because sometimes we don't have lambdas |
| template <typename charT, typename traits> |
| class string_ref_traits_eq { |
| public: |
| string_ref_traits_eq ( charT ch ) : ch_(ch) {} |
| bool operator () ( charT val ) const { return traits::eq ( ch_, val ); } |
| charT ch_; |
| }; |
| } |
| |
| template<typename charT, typename traits> |
| class basic_string_ref { |
| public: |
| // types |
| typedef charT value_type; |
| typedef const charT* pointer; |
| typedef const charT& reference; |
| typedef const charT& const_reference; |
| typedef pointer const_iterator; // impl-defined |
| typedef const_iterator iterator; |
| typedef std::reverse_iterator<const_iterator> const_reverse_iterator; |
| typedef const_reverse_iterator reverse_iterator; |
| typedef std::size_t size_type; |
| typedef std::ptrdiff_t difference_type; |
| static BOOST_CONSTEXPR_OR_CONST size_type npos = size_type(-1); |
| |
| // construct/copy |
| BOOST_CONSTEXPR basic_string_ref () BOOST_NOEXCEPT |
| : ptr_(NULL), len_(0) {} |
| |
| // by defaulting these functions, basic_string_ref becomes |
| // trivially copy/move constructible. |
| BOOST_CONSTEXPR basic_string_ref (const basic_string_ref &rhs) BOOST_NOEXCEPT |
| #ifndef BOOST_STRING_REF_NO_CXX11_DEFAULTED_NOEXCEPT_FUNCTIONS |
| = default; |
| #else |
| : ptr_(rhs.ptr_), len_(rhs.len_) {} |
| #endif |
| |
| basic_string_ref& operator=(const basic_string_ref &rhs) BOOST_NOEXCEPT |
| #ifndef BOOST_STRING_REF_NO_CXX11_DEFAULTED_NOEXCEPT_FUNCTIONS |
| = default; |
| #else |
| { |
| ptr_ = rhs.ptr_; |
| len_ = rhs.len_; |
| return *this; |
| } |
| #endif |
| |
| basic_string_ref(const charT* str) BOOST_NOEXCEPT |
| : ptr_(str), len_(traits::length(str)) {} |
| |
| template<typename Allocator> |
| basic_string_ref(const std::basic_string<charT, traits, Allocator>& str) |
| : ptr_(str.data()), len_(str.length()) {} |
| |
| // #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) && !defined(BOOST_NO_CXX11_DELETED_FUNCTIONS) |
| // // Constructing a string_ref from a temporary string is a bad idea |
| // template<typename Allocator> |
| // basic_string_ref( std::basic_string<charT, traits, Allocator>&&) |
| // = delete; |
| // #endif |
| |
| BOOST_CONSTEXPR basic_string_ref(const charT* str, size_type len) BOOST_NOEXCEPT |
| : ptr_(str), len_(len) {} |
| |
| #ifndef BOOST_NO_CXX11_EXPLICIT_CONVERSION_OPERATORS |
| template<typename Allocator> |
| explicit operator std::basic_string<charT, traits, Allocator>() const { |
| return std::basic_string<charT, traits, Allocator> ( begin(), end()); |
| } |
| #endif |
| |
| std::basic_string<charT, traits> to_string () const { |
| return std::basic_string<charT, traits> ( begin(), end()); |
| } |
| |
| // iterators |
| BOOST_CONSTEXPR const_iterator begin() const { return ptr_; } |
| BOOST_CONSTEXPR const_iterator cbegin() const { return ptr_; } |
| BOOST_CONSTEXPR const_iterator end() const { return ptr_ + len_; } |
| BOOST_CONSTEXPR const_iterator cend() const { return ptr_ + len_; } |
| const_reverse_iterator rbegin() const { return const_reverse_iterator (end()); } |
| const_reverse_iterator crbegin() const { return const_reverse_iterator (end()); } |
| const_reverse_iterator rend() const { return const_reverse_iterator (begin()); } |
| const_reverse_iterator crend() const { return const_reverse_iterator (begin()); } |
| |
| // capacity |
| BOOST_CONSTEXPR size_type size() const { return len_; } |
| BOOST_CONSTEXPR size_type length() const { return len_; } |
| BOOST_CONSTEXPR size_type max_size() const { return len_; } |
| BOOST_CONSTEXPR bool empty() const { return len_ == 0; } |
| |
| // element access |
| BOOST_CONSTEXPR const charT& operator[](size_type pos) const { return ptr_[pos]; } |
| |
| const charT& at(size_t pos) const { |
| if ( pos >= len_ ) |
| BOOST_THROW_EXCEPTION( std::out_of_range ( "boost::string_ref::at" ) ); |
| return ptr_[pos]; |
| } |
| |
| BOOST_CONSTEXPR const charT& front() const { return ptr_[0]; } |
| BOOST_CONSTEXPR const charT& back() const { return ptr_[len_-1]; } |
| BOOST_CONSTEXPR const charT* data() const { return ptr_; } |
| |
| // modifiers |
| void clear() { len_ = 0; } |
| void remove_prefix(size_type n) { |
| if ( n > len_ ) |
| n = len_; |
| ptr_ += n; |
| len_ -= n; |
| } |
| |
| void remove_suffix(size_type n) { |
| if ( n > len_ ) |
| n = len_; |
| len_ -= n; |
| } |
| |
| |
| // basic_string_ref string operations |
| basic_string_ref substr(size_type pos, size_type n=npos) const { |
| if ( pos > size()) |
| BOOST_THROW_EXCEPTION( std::out_of_range ( "string_ref::substr" ) ); |
| return basic_string_ref(data() + pos, (std::min)(size() - pos, n)); |
| } |
| |
| int compare(basic_string_ref x) const { |
| const int cmp = traits::compare ( ptr_, x.ptr_, (std::min)(len_, x.len_)); |
| return cmp != 0 ? cmp : ( len_ == x.len_ ? 0 : len_ < x.len_ ? -1 : 1 ); |
| } |
| |
| bool starts_with(charT c) const { return !empty() && traits::eq ( c, front()); } |
| bool starts_with(basic_string_ref x) const { |
| return len_ >= x.len_ && traits::compare ( ptr_, x.ptr_, x.len_ ) == 0; |
| } |
| |
| bool ends_with(charT c) const { return !empty() && traits::eq ( c, back()); } |
| bool ends_with(basic_string_ref x) const { |
| return len_ >= x.len_ && traits::compare ( ptr_ + len_ - x.len_, x.ptr_, x.len_ ) == 0; |
| } |
| |
| size_type find(basic_string_ref s) const { |
| if (s.empty()) return 0; |
| const_iterator iter = std::search ( this->cbegin (), this->cend (), |
| s.cbegin (), s.cend (), traits::eq ); |
| return iter == this->cend () ? npos : std::distance ( this->cbegin (), iter ); |
| } |
| |
| size_type find(charT c) const { |
| const_iterator iter = std::find_if ( this->cbegin (), this->cend (), |
| detail::string_ref_traits_eq<charT, traits> ( c )); |
| return iter == this->cend () ? npos : std::distance ( this->cbegin (), iter ); |
| } |
| |
| size_type rfind(basic_string_ref s) const { |
| if (s.empty()) return 0; |
| const_reverse_iterator iter = std::search ( this->crbegin (), this->crend (), |
| s.crbegin (), s.crend (), traits::eq ); |
| return iter == this->crend () ? npos : (std::distance(iter, this->crend()) - s.size()); |
| } |
| |
| size_type rfind(charT c) const { |
| const_reverse_iterator iter = std::find_if ( this->crbegin (), this->crend (), |
| detail::string_ref_traits_eq<charT, traits> ( c )); |
| return iter == this->crend () ? npos : (this->size() - 1 - std::distance(this->crbegin(), iter)); |
| } |
| |
| size_type find_first_of(charT c) const { return find (c); } |
| size_type find_last_of (charT c) const { return rfind (c); } |
| |
| size_type find_first_of(basic_string_ref s) const { |
| const_iterator iter = std::find_first_of |
| ( this->cbegin (), this->cend (), s.cbegin (), s.cend (), traits::eq ); |
| return iter == this->cend () ? npos : std::distance ( this->cbegin (), iter ); |
| } |
| |
| size_type find_last_of(basic_string_ref s) const { |
| const_reverse_iterator iter = std::find_first_of |
| ( this->crbegin (), this->crend (), s.cbegin (), s.cend (), traits::eq ); |
| return iter == this->crend () ? npos : (this->size() - 1 - std::distance(this->crbegin(), iter)); |
| } |
| |
| size_type find_first_not_of(basic_string_ref s) const { |
| const_iterator iter = find_not_of ( this->cbegin (), this->cend (), s ); |
| return iter == this->cend () ? npos : std::distance ( this->cbegin (), iter ); |
| } |
| |
| size_type find_first_not_of(charT c) const { |
| for ( const_iterator iter = this->cbegin (); iter != this->cend (); ++iter ) |
| if ( !traits::eq ( c, *iter )) |
| return std::distance ( this->cbegin (), iter ); |
| return npos; |
| } |
| |
| size_type find_last_not_of(basic_string_ref s) const { |
| const_reverse_iterator iter = find_not_of ( this->crbegin (), this->crend (), s ); |
| return iter == this->crend () ? npos : (this->size() - 1 - std::distance(this->crbegin(), iter)); |
| } |
| |
| size_type find_last_not_of(charT c) const { |
| for ( const_reverse_iterator iter = this->crbegin (); iter != this->crend (); ++iter ) |
| if ( !traits::eq ( c, *iter )) |
| return this->size() - 1 - std::distance(this->crbegin(), iter); |
| return npos; |
| } |
| |
| private: |
| |
| template <typename Iterator> |
| Iterator find_not_of ( Iterator first, Iterator last, basic_string_ref s ) const { |
| for ( ; first != last ; ++first ) |
| if ( 0 == traits::find ( s.ptr_, s.len_, *first )) |
| return first; |
| return last; |
| } |
| |
| |
| |
| const charT *ptr_; |
| std::size_t len_; |
| }; |
| |
| |
| // Comparison operators |
| // Equality |
| template<typename charT, typename traits> |
| inline bool operator==(basic_string_ref<charT, traits> x, basic_string_ref<charT, traits> y) { |
| if ( x.size () != y.size ()) return false; |
| return x.compare(y) == 0; |
| } |
| |
| template<typename charT, typename traits, typename Allocator> |
| inline bool operator==(basic_string_ref<charT, traits> x, const std::basic_string<charT, traits, Allocator> & y) { |
| return x == basic_string_ref<charT, traits>(y); |
| } |
| |
| template<typename charT, typename traits, typename Allocator> |
| inline bool operator==(const std::basic_string<charT, traits, Allocator> & x, basic_string_ref<charT, traits> y) { |
| return basic_string_ref<charT, traits>(x) == y; |
| } |
| |
| template<typename charT, typename traits> |
| inline bool operator==(basic_string_ref<charT, traits> x, const charT * y) { |
| return x == basic_string_ref<charT, traits>(y); |
| } |
| |
| template<typename charT, typename traits> |
| inline bool operator==(const charT * x, basic_string_ref<charT, traits> y) { |
| return basic_string_ref<charT, traits>(x) == y; |
| } |
| |
| // Inequality |
| template<typename charT, typename traits> |
| inline bool operator!=(basic_string_ref<charT, traits> x, basic_string_ref<charT, traits> y) { |
| if ( x.size () != y.size ()) return true; |
| return x.compare(y) != 0; |
| } |
| |
| template<typename charT, typename traits, typename Allocator> |
| inline bool operator!=(basic_string_ref<charT, traits> x, const std::basic_string<charT, traits, Allocator> & y) { |
| return x != basic_string_ref<charT, traits>(y); |
| } |
| |
| template<typename charT, typename traits, typename Allocator> |
| inline bool operator!=(const std::basic_string<charT, traits, Allocator> & x, basic_string_ref<charT, traits> y) { |
| return basic_string_ref<charT, traits>(x) != y; |
| } |
| |
| template<typename charT, typename traits> |
| inline bool operator!=(basic_string_ref<charT, traits> x, const charT * y) { |
| return x != basic_string_ref<charT, traits>(y); |
| } |
| |
| template<typename charT, typename traits> |
| inline bool operator!=(const charT * x, basic_string_ref<charT, traits> y) { |
| return basic_string_ref<charT, traits>(x) != y; |
| } |
| |
| // Less than |
| template<typename charT, typename traits> |
| inline bool operator<(basic_string_ref<charT, traits> x, basic_string_ref<charT, traits> y) { |
| return x.compare(y) < 0; |
| } |
| |
| template<typename charT, typename traits, typename Allocator> |
| inline bool operator<(basic_string_ref<charT, traits> x, const std::basic_string<charT, traits, Allocator> & y) { |
| return x < basic_string_ref<charT, traits>(y); |
| } |
| |
| template<typename charT, typename traits, typename Allocator> |
| inline bool operator<(const std::basic_string<charT, traits, Allocator> & x, basic_string_ref<charT, traits> y) { |
| return basic_string_ref<charT, traits>(x) < y; |
| } |
| |
| template<typename charT, typename traits> |
| inline bool operator<(basic_string_ref<charT, traits> x, const charT * y) { |
| return x < basic_string_ref<charT, traits>(y); |
| } |
| |
| template<typename charT, typename traits> |
| inline bool operator<(const charT * x, basic_string_ref<charT, traits> y) { |
| return basic_string_ref<charT, traits>(x) < y; |
| } |
| |
| // Greater than |
| template<typename charT, typename traits> |
| inline bool operator>(basic_string_ref<charT, traits> x, basic_string_ref<charT, traits> y) { |
| return x.compare(y) > 0; |
| } |
| |
| template<typename charT, typename traits, typename Allocator> |
| inline bool operator>(basic_string_ref<charT, traits> x, const std::basic_string<charT, traits, Allocator> & y) { |
| return x > basic_string_ref<charT, traits>(y); |
| } |
| |
| template<typename charT, typename traits, typename Allocator> |
| inline bool operator>(const std::basic_string<charT, traits, Allocator> & x, basic_string_ref<charT, traits> y) { |
| return basic_string_ref<charT, traits>(x) > y; |
| } |
| |
| template<typename charT, typename traits> |
| inline bool operator>(basic_string_ref<charT, traits> x, const charT * y) { |
| return x > basic_string_ref<charT, traits>(y); |
| } |
| |
| template<typename charT, typename traits> |
| inline bool operator>(const charT * x, basic_string_ref<charT, traits> y) { |
| return basic_string_ref<charT, traits>(x) > y; |
| } |
| |
| // Less than or equal to |
| template<typename charT, typename traits> |
| inline bool operator<=(basic_string_ref<charT, traits> x, basic_string_ref<charT, traits> y) { |
| return x.compare(y) <= 0; |
| } |
| |
| template<typename charT, typename traits, typename Allocator> |
| inline bool operator<=(basic_string_ref<charT, traits> x, const std::basic_string<charT, traits, Allocator> & y) { |
| return x <= basic_string_ref<charT, traits>(y); |
| } |
| |
| template<typename charT, typename traits, typename Allocator> |
| inline bool operator<=(const std::basic_string<charT, traits, Allocator> & x, basic_string_ref<charT, traits> y) { |
| return basic_string_ref<charT, traits>(x) <= y; |
| } |
| |
| template<typename charT, typename traits> |
| inline bool operator<=(basic_string_ref<charT, traits> x, const charT * y) { |
| return x <= basic_string_ref<charT, traits>(y); |
| } |
| |
| template<typename charT, typename traits> |
| inline bool operator<=(const charT * x, basic_string_ref<charT, traits> y) { |
| return basic_string_ref<charT, traits>(x) <= y; |
| } |
| |
| // Greater than or equal to |
| template<typename charT, typename traits> |
| inline bool operator>=(basic_string_ref<charT, traits> x, basic_string_ref<charT, traits> y) { |
| return x.compare(y) >= 0; |
| } |
| |
| template<typename charT, typename traits, typename Allocator> |
| inline bool operator>=(basic_string_ref<charT, traits> x, const std::basic_string<charT, traits, Allocator> & y) { |
| return x >= basic_string_ref<charT, traits>(y); |
| } |
| |
| template<typename charT, typename traits, typename Allocator> |
| inline bool operator>=(const std::basic_string<charT, traits, Allocator> & x, basic_string_ref<charT, traits> y) { |
| return basic_string_ref<charT, traits>(x) >= y; |
| } |
| |
| template<typename charT, typename traits> |
| inline bool operator>=(basic_string_ref<charT, traits> x, const charT * y) { |
| return x >= basic_string_ref<charT, traits>(y); |
| } |
| |
| template<typename charT, typename traits> |
| inline bool operator>=(const charT * x, basic_string_ref<charT, traits> y) { |
| return basic_string_ref<charT, traits>(x) >= y; |
| } |
| |
| // Inserter |
| template<class charT, class traits> |
| inline std::basic_ostream<charT, traits>& |
| operator<<(std::basic_ostream<charT, traits>& os, const basic_string_ref<charT,traits>& str) { |
| return boost::io::ostream_put(os, str.data(), str.size()); |
| } |
| |
| #if 0 |
| // numeric conversions |
| // |
| // These are short-term implementations. |
| // In a production environment, I would rather avoid the copying. |
| // |
| inline int stoi (string_ref str, size_t* idx=0, int base=10) { |
| return std::stoi ( std::string(str), idx, base ); |
| } |
| |
| inline long stol (string_ref str, size_t* idx=0, int base=10) { |
| return std::stol ( std::string(str), idx, base ); |
| } |
| |
| inline unsigned long stoul (string_ref str, size_t* idx=0, int base=10) { |
| return std::stoul ( std::string(str), idx, base ); |
| } |
| |
| inline long long stoll (string_ref str, size_t* idx=0, int base=10) { |
| return std::stoll ( std::string(str), idx, base ); |
| } |
| |
| inline unsigned long long stoull (string_ref str, size_t* idx=0, int base=10) { |
| return std::stoull ( std::string(str), idx, base ); |
| } |
| |
| inline float stof (string_ref str, size_t* idx=0) { |
| return std::stof ( std::string(str), idx ); |
| } |
| |
| inline double stod (string_ref str, size_t* idx=0) { |
| return std::stod ( std::string(str), idx ); |
| } |
| |
| inline long double stold (string_ref str, size_t* idx=0) { |
| return std::stold ( std::string(str), idx ); |
| } |
| |
| inline int stoi (wstring_ref str, size_t* idx=0, int base=10) { |
| return std::stoi ( std::wstring(str), idx, base ); |
| } |
| |
| inline long stol (wstring_ref str, size_t* idx=0, int base=10) { |
| return std::stol ( std::wstring(str), idx, base ); |
| } |
| |
| inline unsigned long stoul (wstring_ref str, size_t* idx=0, int base=10) { |
| return std::stoul ( std::wstring(str), idx, base ); |
| } |
| |
| inline long long stoll (wstring_ref str, size_t* idx=0, int base=10) { |
| return std::stoll ( std::wstring(str), idx, base ); |
| } |
| |
| inline unsigned long long stoull (wstring_ref str, size_t* idx=0, int base=10) { |
| return std::stoull ( std::wstring(str), idx, base ); |
| } |
| |
| inline float stof (wstring_ref str, size_t* idx=0) { |
| return std::stof ( std::wstring(str), idx ); |
| } |
| |
| inline double stod (wstring_ref str, size_t* idx=0) { |
| return std::stod ( std::wstring(str), idx ); |
| } |
| |
| inline long double stold (wstring_ref str, size_t* idx=0) { |
| return std::stold ( std::wstring(str), idx ); |
| } |
| #endif |
| |
| } |
| |
| #if 0 |
| namespace std { |
| // Hashing |
| template<> struct hash<boost::string_ref>; |
| template<> struct hash<boost::u16string_ref>; |
| template<> struct hash<boost::u32string_ref>; |
| template<> struct hash<boost::wstring_ref>; |
| } |
| #endif |
| |
| #endif |
