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Frank Astier · Guest

The following small program doesn't compile. I am guessing that this has
something to do with the fact that it doesn't know how to do istream& >>
vector<float>, but I thought I had been careful to tell him how to do that...
What am I missing?

Thanks!

Frank

#include <boost/tuple/tuple.hpp>
#include <boost/tuple/tuple_io.hpp>
#include <iostream>
#include <vector>

template <typename T>
std::istream& operator>>(std::istream& in, std::vector<T>& v)
{ /* appropriate code */ return in; }

struct A : public boost::tuple<std::vector
{
A(std::istream& in) { in >> *this; }
};

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Frank Astier · Guest

Actually, this simpler program has the same compile time error+

#include <boost/tuple/tuple.hpp>
#include <boost/tuple/tuple_io.hpp>
#include <iostream>
#include <vector>

template <typename T>
std::ostream& operator<<(std::ostream& out, const std::vector { return out; }

int main(int, char**)
{
std::vector<int> v;
std::cout << v;

boost::tuple t;
std::cout << t;
}

The error reads:

Compiling with Intel(R) C++ 8.1 ...(Intel C++ Environment)
TestTuples.cpp
C:boost_1_32_0boost/tuple/tuple_io.hpp(255): error: no operator "<<"
matches these operands
operand types are: std::basic_ostream std::char_traits << const boost::tuples::cons std::allocator,
boost::tuples::detail::map_tuple_to_cons<boost::tuples::null_type,
boost::tuples::null_type, boost::tuples::null_type,
boost::tuples::null_type, boost::tuples::null_type,
boost::tuples::null_type, boost::tuples::null_type,
boost::tuples::null_type, boost::tuples::null_type,
boost::tuples::null_type>::type>::stored_head_type
return o << t.head;
^
detected during:
instantiation of "std::basic_ostream<_Elem, _Traits>
&boost::tuples::detail::print(std::basic_ostream<_Elem, _Traits> &,
const boost::tuples::cons<T1, boost::tuples::null_type> &) [with
CharType=char, CharTrait=std::char_traits<char>, T1=std::vector<float,
std::allocator]" at line 321
instantiation of "std::basic_ostream<_Elem, _Traits>
&boost::tuples::operator<<(std::basic_ostream<_Elem, _Traits> &, const
boost::tuples::cons<T1, T2> &) [with CharType=char,
CharTrait=std::char_traits<char>, T1=std::vector<float,
std::allocator,
T2=boost::tuples::detail::map_tuple_to_cons<boost::tuples::null_type,
boost::tuples::null_type, boost::tuples::null_type,
boost::tuples::null_type, boost::tuples::null_type,
boost::tuples::null_type, boost::tuples::null_type,
boost::tuples::null_type,
boost::tuples::null_type, boost::tuples::null_type>::type]"
compilation aborted for .TestTuples.cpp (code 2)

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