explicit basic_istringstream(ios_base::openmode which = ios_base::in);
Effects: Constructs an object of class basic_istringstream<charT, traits>, initializing the base class with basic_istream(&sb) and initializing sb with basic_stringbuf<charT, traits, Allocator>(which | ios_base::in)) ([stringbuf.cons]).
explicit basic_istringstream(
const basic_string<charT, traits, Allocator>& str,
ios_base::openmode which = ios_base::in);
Effects: Constructs an object of class basic_istringstream<charT, traits>, initializing the base class with basic_istream(&sb) and initializing sb with basic_stringbuf<charT, traits, Allocator>(str, which | ios_base::in)) ([stringbuf.cons]).
basic_istringstream(basic_istringstream&& rhs);
Effects: Move constructs from the rvalue rhs. This is accomplished by move constructing the base class, and the contained basic_stringbuf. Next basic_istream<charT,traits>::set_rdbuf(&sb) is called to install the contained basic_stringbuf.