Standard library header <sstream>

 

C++

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Freestanding and hosted

Language

Standard library headers

Named requirements

Feature test macros (C++20)

Language support library

Concepts library (C++20)

Diagnostics library

General utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Localizations library

Input/output library

Filesystem library (C++17)

Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

Technical specifications

Symbols index

External libraries

 

Standard Library headers

Language Support
<cstddef> <cstdlib> <version> <limits> <climits>	<cfloat> <cstdint> <new> <typeinfo>	<source_location> <exception> <initializer_list>     <compare>	<coroutine> <csignal> <csetjmp> <cstdarg>
Concepts
<concepts>
Diagnostics
<stdexcept>	<cassert>	<cerrno>	<system_error>
General utilities
<utility> <memory> <memory_resource> <scoped_allocator>	<bitset> <tuple> <optional> <any>	<variant> <type_traits> <ratio> <chrono>	<typeindex> <functional> <stacktrace> <ctime>
Strings
<string> <string_view> <cstring>	<charconv> <format>	<cctype> <cwctype>	<cwchar> <cuchar>
Localization
<locale>	<codecvt>	<clocale>
Containers
<span> <array> <vector>	<deque> <forward_list> <list>	<map> <set> <queue>	<unordered_map> <unordered_set> <stack>
Iterators
<iterator>
Ranges
<ranges>
Algorithms
<algorithm>	<execution>
Numerics
<complex> <random>	<valarray> <numeric>	<bit> <numbers>	<cfenv> <cmath>
Input/Output
<iosfwd> <ios> <iomanip> <streambuf>	<istream> <ostream> <iostream>	<sstream> <spanstream> <fstream> <syncstream>	<cstdio> <cinttypes> <strstream>
Regular expressions
<regex>
Filesystem support
<filesystem>
Thread support
<thread> <atomic> <mutex>	<shared_mutex> <condition_variable>     <future>	<stop_token> <semaphore>	<latch> <barrier>
C compatibility
<ciso646> <cstdalign>	<cstdbool> <ccomplex>	<ctgmath> <stdatomic.h>

 

This header is part of the Input/Output library.

Classes
basic_stringbuf	implements raw string device (class template)
basic_istringstream	implements high-level string stream input operations (class template)
basic_ostringstream	implements high-level string stream output operations (class template)
basic_stringstream	implements high-level string stream input/output operations (class template)
stringbuf	std::basic_stringbuf<char> (typedef)
wstringbuf	std::basic_stringbuf<wchar_t> (typedef)
istringstream	std::basic_istringstream<char> (typedef)
wistringstream	std::basic_istringstream<wchar_t> (typedef)
ostringstream	std::basic_ostringstream<char> (typedef)
wostringstream	std::basic_ostringstream<wchar_t> (typedef)
stringstream	std::basic_stringstream<char> (typedef)
wstringstream	std::basic_stringstream<wchar_t> (typedef)
Functions
std::swap(std::basic_stringbuf) (C++11)	specializes the std::swap algorithm (function template)
std::swap(std::basic_istringstream) (C++11)	specializes the std::swap algorithm (function template)
std::swap(std::basic_ostringstream) (C++11)	specializes the std::swap algorithm (function template)
std::swap(std::basic_stringstream) (C++11)	specializes the std::swap algorithm (function template)

Synopsis

namespace std {
  template<class CharT, class Traits = char_traits<CharT>,
           class Allocator = allocator<CharT>>
    class basic_stringbuf;
 
  using stringbuf  = basic_stringbuf<char>;
  using wstringbuf = basic_stringbuf<wchar_t>;
 
  template<class CharT, class Traits = char_traits<CharT>,
           class Allocator = allocator<CharT>>
    class basic_istringstream;
 
  using istringstream  = basic_istringstream<char>;
  using wistringstream = basic_istringstream<wchar_t>;
 
  template<class CharT, class Traits = char_traits<CharT>,
           class Allocator = allocator<CharT>>
    class basic_ostringstream;
  using ostringstream  = basic_ostringstream<char>;
  using wostringstream = basic_ostringstream<wchar_t>;
 
  template<class CharT, class Traits = char_traits<CharT>,
           class Allocator = allocator<CharT>>
    class basic_stringstream;
  using stringstream  = basic_stringstream<char>;
  using wstringstream = basic_stringstream<wchar_t>;
}

Class template std::basic_stringbuf

namespace std {
  template<class CharT, class Traits = char_traits<CharT>,
           class Allocator = allocator<CharT>>
  class basic_stringbuf : public basic_streambuf<CharT, Traits> {
  public:
    using char_type      = CharT;
    using int_type       = typename Traits::int_type;
    using pos_type       = typename Traits::pos_type;
    using off_type       = typename Traits::off_type;
    using Traits_type    = Traits;
    using allocator_type = Allocator;
 
    // constructors
    basic_stringbuf() : basic_stringbuf(ios_base::in | ios_base::out) {}
    explicit basic_stringbuf(ios_base::openmode which);
    explicit basic_stringbuf(
      const basic_string<CharT, Traits, Allocator>& s,
      ios_base::openmode which = ios_base::in | ios_base::out);
    explicit basic_stringbuf(const Allocator& a)
      : basic_stringbuf(ios_base::in | ios_base::out, a) {}
    basic_stringbuf(ios_base::openmode which, const Allocator& a);
    explicit basic_stringbuf(
      basic_string<CharT, Traits, Allocator>&& s,
      ios_base::openmode which = ios_base::in | ios_base::out);
    template<class SAlloc>
      basic_stringbuf(
        const basic_string<CharT, Traits, SAlloc>& s, const Allocator& a)
        : basic_stringbuf(s, ios_base::in | ios_base::out, a) {}
    template<class SAlloc>
      basic_stringbuf(
        const basic_string<CharT, Traits, SAlloc>& s,
        ios_base::openmode which, const Allocator& a);
    template<class SAlloc>
      explicit basic_stringbuf(
        const basic_string<CharT, Traits, SAlloc>& s,
        ios_base::openmode which = ios_base::in | ios_base::out);
    basic_stringbuf(const basic_stringbuf&) = delete;
    basic_stringbuf(basic_stringbuf&& rhs);
    basic_stringbuf(basic_stringbuf&& rhs, const Allocator& a);
 
    // assign and swap
    basic_stringbuf& operator=(const basic_stringbuf&) = delete;
    basic_stringbuf& operator=(basic_stringbuf&& rhs);
    void swap(basic_stringbuf& rhs) noexcept(see below);
 
    // getters and setters
    allocator_type get_allocator() const noexcept;
 
    basic_string<CharT, Traits, Allocator> str() const &;
    template<class SAlloc>
      basic_string<CharT,Traits,SAlloc> str(const SAlloc& sa) const;
    basic_string<CharT, Traits, Allocator> str() &&;
    basic_string_view<CharT, Traits> view() const noexcept;
 
    void str(const basic_string<CharT, Traits, Allocator>& s);
    template<class SAlloc>
      void str(const basic_string<CharT, Traits, SAlloc>& s);
    void str(basic_string<CharT, Traits, Allocator>&& s);
 
  protected:
    // overridden virtual functions
    int_type underflow() override;
    int_type pbackfail(int_type c = Traits::eof()) override;
    int_type overflow (int_type c = Traits::eof()) override;
    basic_streambuf<CharT, Traits>* setbuf(CharT*, streamsize) override;
 
    pos_type seekoff(off_type off, ios_base::seekdir way,
                     ios_base::openmode which
                      = ios_base::in | ios_base::out) override;
    pos_type seekpos(pos_type sp,
                     ios_base::openmode which
                      = ios_base::in | ios_base::out) override;
 
  private:
    ios_base::openmode mode;                        // exposition only
    basic_string<CharT, Traits, Allocator> buf;     // exposition only
    void init_buf_ptrs();                           // exposition only
  };
 
  template<class CharT, class Traits, class Allocator>
    void swap(basic_stringbuf<CharT, Traits, Allocator>& x,
              basic_stringbuf<CharT, Traits, Allocator>& y) noexcept(noexcept(x.swap(y)));
}

Class template std::basic_istringstream

namespace std {
  template<class CharT, class Traits = char_traits<CharT>,
           class Allocator = allocator<CharT>>
  class basic_istringstream : public basic_istream<CharT, Traits> {
  public:
    using char_type      = CharT;
    using int_type       = typename Traits::int_type;
    using pos_type       = typename Traits::pos_type;
    using off_type       = typename Traits::off_type;
    using Traits_type    = Traits;
    using allocator_type = Allocator;
 
    // constructors
    basic_istringstream() : basic_istringstream(ios_base::in) {}
    explicit basic_istringstream(ios_base::openmode which);
    explicit basic_istringstream(
      const basic_string<CharT, Traits, Allocator>& s,
      ios_base::openmode which = ios_base::in);
    basic_istringstream(ios_base::openmode which, const Allocator& a);
    explicit basic_istringstream(
      basic_string<CharT, Traits, Allocator>&& s,
      ios_base::openmode which = ios_base::in);
    template<class SAlloc>
      basic_istringstream(
        const basic_string<CharT, Traits, SAlloc>& s, const Allocator& a)
        : basic_istringstream(s, ios_base::in, a) {}
    template<class SAlloc>
      basic_istringstream(
        const basic_string<CharT, Traits, SAlloc>& s,
        ios_base::openmode which, const Allocator& a);
    template<class SAlloc>
      explicit basic_istringstream(
        const basic_string<CharT, Traits, SAlloc>& s,
        ios_base::openmode which = ios_base::in);
    basic_istringstream(const basic_istringstream&) = delete;
    basic_istringstream(basic_istringstream&& rhs);
 
    // assign and swap
    basic_istringstream& operator=(const basic_istringstream&) = delete;
    basic_istringstream& operator=(basic_istringstream&& rhs);
    void swap(basic_istringstream& rhs);
 
    // members
    basic_stringbuf<CharT, Traits, Allocator>* rdbuf() const;
    basic_string<CharT, Traits, Allocator> str() const &;
    template<class SAlloc>
      basic_string<CharT,Traits,SAlloc> str(const SAlloc& sa) const;
    basic_string<CharT, Traits, Allocator> str() &&;
    basic_string_view<CharT, Traits> view() const noexcept;
 
    void str(const basic_string<CharT, Traits, Allocator>& s);
    template<class SAlloc>
      void str(const basic_string<CharT, Traits, SAlloc>& s);
    void str(basic_string<CharT, Traits, Allocator>&& s);
 
  private:
    basic_stringbuf<CharT, Traits, Allocator> sb;   // exposition only
  };
 
  template<class CharT, class Traits, class Allocator>
    void swap(basic_istringstream<CharT, Traits, Allocator>& x,
              basic_istringstream<CharT, Traits, Allocator>& y);
}

Class template std::basic_ostringstream

namespace std {
  template<class CharT, class Traits = char_traits<CharT>,
           class Allocator = allocator<CharT>>
  class basic_ostringstream : public basic_ostream<CharT, Traits> {
  public:
    using char_type      = CharT;
    using int_type       = typename Traits::int_type;
    using pos_type       = typename Traits::pos_type;
    using off_type       = typename Traits::off_type;
    using Traits_type    = Traits;
    using allocator_type = Allocator;
 
    // constructors
    basic_ostringstream() : basic_ostringstream(ios_base::out) {}
    explicit basic_ostringstream(ios_base::openmode which);
    explicit basic_ostringstream(
      const basic_string<CharT, Traits, Allocator>& s,
      ios_base::openmode which = ios_base::out);
    basic_ostringstream(ios_base::openmode which, const Allocator& a);
    explicit basic_ostringstream(
      basic_string<CharT, Traits, Allocator>&& s,
      ios_base::openmode which = ios_base::out);
    template<class SAlloc>
      basic_ostringstream(
        const basic_string<CharT, Traits, SAlloc>& s, const Allocator& a)
        : basic_ostringstream(s, ios_base::out, a) {}
    template<class SAlloc>
      basic_ostringstream(
        const basic_string<CharT, Traits, SAlloc>& s,
        ios_base::openmode which, const Allocator& a);
    template<class SAlloc>
      explicit basic_ostringstream(
        const basic_string<CharT, Traits, SAlloc>& s,
        ios_base::openmode which = ios_base::out);
    basic_ostringstream(const basic_ostringstream&) = delete;
    basic_ostringstream(basic_ostringstream&& rhs);
 
    // assign and swap
    basic_ostringstream& operator=(const basic_ostringstream&) = delete;
    basic_ostringstream& operator=(basic_ostringstream&& rhs);
    void swap(basic_ostringstream& rhs);
 
    // members
    basic_stringbuf<CharT, Traits, Allocator>* rdbuf() const;
 
    basic_string<CharT, Traits, Allocator> str() const &;
    template<class SAlloc>
      basic_string<CharT,Traits,SAlloc> str(const SAlloc& sa) const;
    basic_string<CharT, Traits, Allocator> str() &&;
    basic_string_view<CharT, Traits> view() const noexcept;
 
    void str(const basic_string<CharT, Traits, Allocator>& s);
    template<class SAlloc>
      void str(const basic_string<CharT, Traits, SAlloc>& s);
    void str(basic_string<CharT, Traits, Allocator>&& s);
 
   private:
    basic_stringbuf<CharT, Traits, Allocator> sb;   // exposition only
  };
 
  template<class CharT, class Traits, class Allocator>
    void swap(basic_ostringstream<CharT, Traits, Allocator>& x,
              basic_ostringstream<CharT, Traits, Allocator>& y);
}

Class template std::basic_stringstream

namespace std {
  template<class CharT, class Traits = char_traits<CharT>,
           class Allocator = allocator<CharT>>
  class basic_stringstream : public basic_iostream<CharT, Traits> {
  public:
    using char_type      = CharT;
    using int_type       = typename Traits::int_type;
    using pos_type       = typename Traits::pos_type;
    using off_type       = typename Traits::off_type;
    using Traits_type    = Traits;
    using allocator_type = Allocator;
 
    // constructors
    basic_stringstream() : basic_stringstream(ios_base::out | ios_base::in) {}
    explicit basic_stringstream(ios_base::openmode which);
    explicit basic_stringstream(
      const basic_string<CharT, Traits, Allocator>& s,
      ios_base::openmode which = ios_base::out | ios_base::in);
    basic_stringstream(ios_base::openmode which, const Allocator& a);
    explicit basic_stringstream(
      basic_string<CharT, Traits, Allocator>&& s,
      ios_base::openmode which = ios_base::out | ios_base::in);
    template<class SAlloc>
      basic_stringstream(
        const basic_string<CharT, Traits, SAlloc>& s, const Allocator& a)
        : basic_stringstream(s, ios_base::out | ios_base::in, a) {}
    template<class SAlloc>
      basic_stringstream(
        const basic_string<CharT, Traits, SAlloc>& s,
        ios_base::openmode which, const Allocator& a);
    template<class SAlloc>
      explicit basic_stringstream(
        const basic_string<CharT, Traits, SAlloc>& s,
        ios_base::openmode which = ios_base::out | ios_base::in);
    basic_stringstream(const basic_stringstream&) = delete;
    basic_stringstream(basic_stringstream&& rhs);
 
    // assign and swap
    basic_stringstream& operator=(const basic_stringstream&) = delete;
    basic_stringstream& operator=(basic_stringstream&& rhs);
    void swap(basic_stringstream& rhs);
 
    // members
    basic_stringbuf<CharT, Traits, Allocator>* rdbuf() const;
 
    basic_string<CharT, Traits, Allocator> str() const &;
    template<class SAlloc>
      basic_string<CharT,Traits,SAlloc> str(const SAlloc& sa) const;
    basic_string<CharT, Traits, Allocator> str() &&;
    basic_string_view<CharT, Traits> view() const noexcept;
 
    void str(const basic_string<CharT, Traits, Allocator>& s);
    template<class SAlloc>
      void str(const basic_string<CharT, Traits, SAlloc>& s);
    void str(basic_string<CharT, Traits, Allocator>&& s);
 
  private:
    basic_stringbuf<CharT, Traits> sb;  // exposition only
  };
 
  template<class CharT, class Traits, class Allocator>
    void swap(basic_stringstream<CharT, Traits, Allocator>& x,
              basic_stringstream<CharT, Traits, Allocator>& y);
}