Hi, Take this code: #include <string> #include <boost/tuple/tuple.hpp> struct A {}; bool operator==(A, A) { return true; } int main() { using namespace boost; tuple<std::string, int, A> t1(std::string("same?"), 2, A()); tuple<std::string, long, A> t2(std::string("same?"), 2, A()); tuple<std::string, long, A> t3(std::string("different"), 3, A()); t1 == t2; // error: no match for operator== t1 == t3; // error: no match for operator== } This is similar to the example shown in Boost.Tuple docs. However the compiler(*) refuses to compile it. I tried it with versions 1.33.0 and 1.33.1 (Beta) Any ideas? Compiler outputs below: MSC C/C++ Compiler 13.10;3077 cl /GR /EHsc /IE:\projects\libraries\boost_1_33_1 tuple_error.cpp Microsoft (R) 32-bit C/C++ Optimizing Compiler Version 13.10.3077 for 80x86 Copyright (C) Microsoft Corporation 1984-2002. All rights reserved. tuple_error.cpp tuple_error.cpp(17) : error C2678: binary '==' : no operator found which takes a left-hand operand of type 'boost::tuples::tuple<T0,T1,T2>' (or there is no acce ptable conversion) with [ T0=std::string, T1=int, T2=A ] tuple_error.cpp(18) : error C2678: binary '==' : no operator found which takes a left-hand operand of type 'boost::tuples::tuple<T0,T1,T2>' (or there is no acce ptable conversion) with [ T0=std::string, T1=int, T2=A ] gcc 3.4.4 g++ -I E:\projects\libraries\boost_1_33_1 tuple_error.cpp -o tuple_error_gcc.exe tuple_error.cpp: In function `int main()': tuple_error.cpp:17: error: no match for 'operator==' in 't1 == t2' tuple_error.cpp:7: note: candidates are: bool operator==(A, A) tuple_error.cpp:18: error: no match for 'operator==' in 't1 == t3' tuple_error.cpp:7: note: candidates are: bool operator==(A, A) Regards, Josue