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//===----------------------------------------------------------------------===//
//
// ÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊThe LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// <istream>
// template <class charT, class traits = char_traits<charT> >
// class basic_istream;
// operator>>(long long& val);
#include <istream>
#include <cassert>
template <class CharT>
struct testbuf
: public std::basic_streambuf<CharT>
{
typedef std::basic_string<CharT> string_type;
typedef std::basic_streambuf<CharT> base;
private:
string_type str_;
public:
testbuf() {}
testbuf(const string_type& str)
: str_(str)
{
base::setg(const_cast<CharT*>(str_.data()),
const_cast<CharT*>(str_.data()),
const_cast<CharT*>(str_.data()) + str_.size());
}
CharT* eback() const {return base::eback();}
CharT* gptr() const {return base::gptr();}
CharT* egptr() const {return base::egptr();}
};
int main()
{
{
std::istream is((std::streambuf*)0);
long long n = 0;
is >> n;
assert(is.fail());
}
{
testbuf<char> sb("0");
std::istream is(&sb);
long long n = 10;
is >> n;
assert(n == 0);
assert( is.eof());
assert(!is.fail());
}
{
testbuf<char> sb(" 123 ");
std::istream is(&sb);
long long n = 10;
is >> n;
assert(n == 123);
assert(!is.eof());
assert(!is.fail());
}
{
testbuf<wchar_t> sb(L" -123 ");
std::wistream is(&sb);
long long n = 10;
is >> n;
assert(n == -123);
assert(!is.eof());
assert(!is.fail());
}
}
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