29 Input/output library [input.output]

29.8 String-based streams [string.streams]

29.8.3 Class template basic_istringstream [istringstream]

29.8.3.2 Assignment and swap [istringstream.assign]

void swap(basic_istringstream& rhs);

Effects: Equivalent to:

basic_istream<charT, traits>::swap(rhs);
sb.swap(rhs.sb);

template<class charT, class traits, class Allocator>
  void swap(basic_istringstream<charT, traits, Allocator>& x,
            basic_istringstream<charT, traits, Allocator>& y);

Effects: Equivalent to: x.swap(y).