Happy Holidays to everyone! I am getting aquainted with the tuple class but am encountering the following error: c:\BGL\boost_1_29_0\boost\tuple\tuple_comparison.hpp(119): error C2027: use of undefined type 'boost::STATIC_ASSERTION_FAILURE<x>' with [ x=false ] with the following program: /** * tupleTest.cpp * Test of Boost library class tuple * A tuple is a fixed size collection of elements * Stored objects may be of different types * Current support of tuples with 0-10 objects * Objects may be any valid C++ type except void and function types * Jon Agiato * 12-23-02 */ #include <iostream> using std::cout; using std::cin; using std::ostream; using std::cerr; #include <cstdlib> #include using boost::tuple; // both tuple_io.hpp and tuple_comparison.hpp include tuple.hpp // tuple_io must be included for tuple input and output operators #include // tuple_comparison.hpp must be included for comparison operators #include #include <string> using std::string; #include <exception> using std::exception; class A { friend ostream &operator<<(ostream &output, const A &a) { output << a.S; return output; } public: A(string s = "Testing"):S(s) {;} string S; }; class B { friend ostream &operator<<(ostream &output, const B &b) { output << b.D; return output; } public: B(double d = 3.501):D(d) {;} double D; }; class C { friend ostream &operator<<(ostream &output, const C &c) { output << c.state; return output; } public: C(bool st = true):state(st) {;} double state; }; int main() { try { tuple testTuple; cout << testTuple << '\n'; tuple test2Tuple; if(testTuple == test2Tuple) cout << testTuple << " is equal to " << test2Tuple << '\n'; else cout << testTuple << " is not equal to " << test2Tuple << '\n'; cout << "Press enter to exit..."; cin.get(); return EXIT_SUCCESS; } catch(const exception &E) { cerr << "Standard library exception: " << E.what() << '\n'; return EXIT_FAILURE; } catch(...) { cerr << "Unknown exception thrown.\n"; return EXIT_FAILURE; } } I am using Visual Studio.NET Enterprise Architect Thanks! Jon Agiato JonAgiato@nyc.rr.com