24 Strings library [strings]

24.3 String classes [string.classes]

24.3.1 Header <string> synopsis [string.syn]

#include <initializer_list>

namespace std {
  // [char.traits], character traits
  template<class charT> struct char_traits;
  template<> struct char_traits<char>;
  template<> struct char_traits<char16_t>;
  template<> struct char_traits<char32_t>;
  template<> struct char_traits<wchar_t>;

  // [basic.string], basic_­string
  template<class charT, class traits = char_traits<charT>, class Allocator = allocator<charT>>
    class basic_string;

  template<class charT, class traits, class Allocator>
    basic_string<charT, traits, Allocator>
      operator+(const basic_string<charT, traits, Allocator>& lhs,
                const basic_string<charT, traits, Allocator>& rhs);
  template<class charT, class traits, class Allocator>
    basic_string<charT, traits, Allocator>
      operator+(basic_string<charT, traits, Allocator>&& lhs,
                const basic_string<charT, traits, Allocator>& rhs);
  template<class charT, class traits, class Allocator>
    basic_string<charT, traits, Allocator>
      operator+(const basic_string<charT, traits, Allocator>& lhs,
                basic_string<charT, traits, Allocator>&& rhs);
  template<class charT, class traits, class Allocator>
    basic_string<charT, traits, Allocator>
      operator+(basic_string<charT, traits, Allocator>&& lhs,
                basic_string<charT, traits, Allocator>&& rhs);
  template<class charT, class traits, class Allocator>
    basic_string<charT, traits, Allocator>
      operator+(const charT* lhs,
                const basic_string<charT, traits, Allocator>& rhs);
  template<class charT, class traits, class Allocator>
    basic_string<charT, traits, Allocator>
      operator+(const charT* lhs,
                basic_string<charT, traits, Allocator>&& rhs);
  template<class charT, class traits, class Allocator>
    basic_string<charT, traits, Allocator>
      operator+(charT lhs, const basic_string<charT, traits, Allocator>& rhs);
  template<class charT, class traits, class Allocator>
    basic_string<charT, traits, Allocator>
      operator+(charT lhs, basic_string<charT, traits, Allocator>&& rhs);
  template<class charT, class traits, class Allocator>
    basic_string<charT, traits, Allocator>
      operator+(const basic_string<charT, traits, Allocator>& lhs,
                const charT* rhs);
  template<class charT, class traits, class Allocator>
    basic_string<charT, traits, Allocator>
      operator+(basic_string<charT, traits, Allocator>&& lhs,
                const charT* rhs);
  template<class charT, class traits, class Allocator>
    basic_string<charT, traits, Allocator>
      operator+(const basic_string<charT, traits, Allocator>& lhs, charT rhs);
  template<class charT, class traits, class Allocator>
    basic_string<charT, traits, Allocator>
      operator+(basic_string<charT, traits, Allocator>&& lhs, charT rhs);

  template<class charT, class traits, class Allocator>
    bool operator==(const basic_string<charT, traits, Allocator>& lhs,
                    const basic_string<charT, traits, Allocator>& rhs) noexcept;
  template<class charT, class traits, class Allocator>
    bool operator==(const charT* lhs,
                    const basic_string<charT, traits, Allocator>& rhs);
  template<class charT, class traits, class Allocator>
    bool operator==(const basic_string<charT, traits, Allocator>& lhs,
                    const charT* rhs);
  template<class charT, class traits, class Allocator>
    bool operator!=(const basic_string<charT, traits, Allocator>& lhs,
                    const basic_string<charT, traits, Allocator>& rhs) noexcept;
  template<class charT, class traits, class Allocator>
    bool operator!=(const charT* lhs,
                    const basic_string<charT, traits, Allocator>& rhs);
  template<class charT, class traits, class Allocator>
    bool operator!=(const basic_string<charT, traits, Allocator>& lhs,
                    const charT* rhs);

  template<class charT, class traits, class Allocator>
    bool operator< (const basic_string<charT, traits, Allocator>& lhs,
                    const basic_string<charT, traits, Allocator>& rhs) noexcept;
  template<class charT, class traits, class Allocator>
    bool operator< (const basic_string<charT, traits, Allocator>& lhs,
                    const charT* rhs);
  template<class charT, class traits, class Allocator>
    bool operator< (const charT* lhs,
                    const basic_string<charT, traits, Allocator>& rhs);
  template<class charT, class traits, class Allocator>
    bool operator> (const basic_string<charT, traits, Allocator>& lhs,
                    const basic_string<charT, traits, Allocator>& rhs) noexcept;
  template<class charT, class traits, class Allocator>
    bool operator> (const basic_string<charT, traits, Allocator>& lhs,
                    const charT* rhs);
  template<class charT, class traits, class Allocator>
    bool operator> (const charT* lhs,
                    const basic_string<charT, traits, Allocator>& rhs);

  template<class charT, class traits, class Allocator>
    bool operator<=(const basic_string<charT, traits, Allocator>& lhs,
                    const basic_string<charT, traits, Allocator>& rhs) noexcept;
  template<class charT, class traits, class Allocator>
    bool operator<=(const basic_string<charT, traits, Allocator>& lhs,
                    const charT* rhs);
  template<class charT, class traits, class Allocator>
    bool operator<=(const charT* lhs,
                    const basic_string<charT, traits, Allocator>& rhs);
  template<class charT, class traits, class Allocator>
    bool operator>=(const basic_string<charT, traits, Allocator>& lhs,
                    const basic_string<charT, traits, Allocator>& rhs) noexcept;
  template<class charT, class traits, class Allocator>
    bool operator>=(const basic_string<charT, traits, Allocator>& lhs,
                    const charT* rhs);
  template<class charT, class traits, class Allocator>
    bool operator>=(const charT* lhs,
                    const basic_string<charT, traits, Allocator>& rhs);

  // [string.special], swap
  template<class charT, class traits, class Allocator>
    void swap(basic_string<charT, traits, Allocator>& lhs,
              basic_string<charT, traits, Allocator>& rhs)
      noexcept(noexcept(lhs.swap(rhs)));

  // [string.io], inserters and extractors
  template<class charT, class traits, class Allocator>
    basic_istream<charT, traits>&
      operator>>(basic_istream<charT, traits>& is,
                 basic_string<charT, traits, Allocator>& str);
  template<class charT, class traits, class Allocator>
    basic_ostream<charT, traits>&
      operator<<(basic_ostream<charT, traits>& os,
                 const basic_string<charT, traits, Allocator>& str);
  template<class charT, class traits, class Allocator>
    basic_istream<charT, traits>&
      getline(basic_istream<charT, traits>& is,
              basic_string<charT, traits, Allocator>& str,
              charT delim);
  template<class charT, class traits, class Allocator>
    basic_istream<charT, traits>&
      getline(basic_istream<charT, traits>&& is,
              basic_string<charT, traits, Allocator>& str,
              charT delim);
  template<class charT, class traits, class Allocator>
    basic_istream<charT, traits>&
      getline(basic_istream<charT, traits>& is,
              basic_string<charT, traits, Allocator>& str);
  template<class charT, class traits, class Allocator>
    basic_istream<charT, traits>&
      getline(basic_istream<charT, traits>&& is,
              basic_string<charT, traits, Allocator>& str);

  // basic_­string typedef names
  using string    = basic_string<char>;
  using u16string = basic_string<char16_t>;
  using u32string = basic_string<char32_t>;
  using wstring   = basic_string<wchar_t>;

  // [string.conversions], numeric conversions
  int stoi(const string& str, size_t* idx = nullptr, int base = 10);
  long stol(const string& str, size_t* idx = nullptr, int base = 10);
  unsigned long stoul(const string& str, size_t* idx = nullptr, int base = 10);
  long long stoll(const string& str, size_t* idx = nullptr, int base = 10);
  unsigned long long stoull(const string& str, size_t* idx = nullptr, int base = 10);
  float stof(const string& str, size_t* idx = nullptr);
  double stod(const string& str, size_t* idx = nullptr);
  long double stold(const string& str, size_t* idx = nullptr);
  string to_string(int val);
  string to_string(unsigned val);
  string to_string(long val);
  string to_string(unsigned long val);
  string to_string(long long val);
  string to_string(unsigned long long val);
  string to_string(float val);
  string to_string(double val);
  string to_string(long double val);

  int stoi(const wstring& str, size_t* idx = nullptr, int base = 10);
  long stol(const wstring& str, size_t* idx = nullptr, int base = 10);
  unsigned long stoul(const wstring& str, size_t* idx = nullptr, int base = 10);
  long long stoll(const wstring& str, size_t* idx = nullptr, int base = 10);
  unsigned long long stoull(const wstring& str, size_t* idx = nullptr, int base = 10);
  float stof(const wstring& str, size_t* idx = nullptr);
  double stod(const wstring& str, size_t* idx = nullptr);
  long double stold(const wstring& str, size_t* idx = nullptr);
  wstring to_wstring(int val);
  wstring to_wstring(unsigned val);
  wstring to_wstring(long val);
  wstring to_wstring(unsigned long val);
  wstring to_wstring(long long val);
  wstring to_wstring(unsigned long long val);
  wstring to_wstring(float val);
  wstring to_wstring(double val);
  wstring to_wstring(long double val);

  // [basic.string.hash], hash support
  template<class T> struct hash;
  template<> struct hash<string>;
  template<> struct hash<u16string>;
  template<> struct hash<u32string>;
  template<> struct hash<wstring>;

  namespace pmr {
    template <class charT, class traits = char_traits<charT>>
      using basic_string = std::basic_string<charT, traits, polymorphic_allocator<charT>>;

    using string    = basic_string<char>;
    using u16string = basic_string<char16_t>;
    using u32string = basic_string<char32_t>;
    using wstring   = basic_string<wchar_t>;
  }

  inline namespace literals {
  inline namespace string_literals {
    // [basic.string.literals], suffix for basic_­string literals
    string    operator""s(const char* str, size_t len);
    u16string operator""s(const char16_t* str, size_t len);
    u32string operator""s(const char32_t* str, size_t len);
    wstring   operator""s(const wchar_t* str, size_t len);
  }
  }
}