template<class E, class T, class A>
basic_istream<E, T>& operator>>(
basic_istream <E, T>& is,
const basic_string<E, T, A>& str);
The template function overloads operator>> to replace the sequence controlled by str with a sequence of elements
extracted from the stream is. Extraction stops:
is.width() elements, if that value is nonzero.is.max_size() elements.c for which use_facet< ctype<E> >( getloc()). is(
ctype<E>::space, c) is true, in which case the character is put back.If the function extracts no elements, it calls setstate(ios_base::failbit). In any case, it calls width(0) and
returns *this.
See the related sample program.