Sorry, never got a reply in the users list, So fwd'ed here... -------- Original Message -------- Subject: lexical_cast problem Date: Fri, 4 Aug 2006 16:53:10 +1200 From: shams <shams@orcon.net.nz> To: boost-users@lists.boost.org Hi, Here is a sample custom string class that I am tring to get working with lexical_cast but it gives me compile errors. Can you please see what I am doing wrong here. More explanation below. OTOH if I use a custom lexical_cast using wstringstream it works fine. // main.cpp #include <string> #include <iostream> #include "boost_1_33_1/boost/lexical_cast.hpp" using namespace std; class String : public wstring { public: String() { } String(const wchar_t *str) : wstring(str) { } String& operator=(const String& Rhs) { return static_cast<String&>(wstring::operator=(Rhs)); } }; // This is commented cause lexical_cast wants bool return value. #if 0 template<class OutputStream> OutputStream& operator<<(OutputStream &o, const String &s) { return o << s.c_str(); } #endif template<class OutputStream> bool operator<<(OutputStream &o, const String &s) { o << s.c_str(); return true; } // This is commented cause lexical_cast wants bool return value. #if 0 template<class InputStream> InputStream& operator>>(InputStream &i, String &s) { wstring ws; i >> ws; s.assign(ws); return i; } #endif template<class InputStream> bool operator>>(InputStream &i, String &s) { wstring ws; i >> ws; s.assign(ws); return true; } int main() { // This line causes errors both on MSVC and GCC. wcout << boost::lexical_cast<String>(10); // These lines DONT cause errors and work ok. String s = L"hello"; wcout << s; wcout << endl; wcin >> s; wcout << s; wcout << endl; return 0; }