c++ - Overloading operator<< for endl using templates -

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i have class inherits ofstream. want overload insertion operator can drop in repalcement ofstream.

the first overload is

template<class t> myclass& myclass::operator<<(const t& in);

and try , handle manipulators std::endl

template<     template<class, class> class outer,     class inner1,      class inner2 > myclass& myclass::operator<<(outer<inner1, inner2>& (*foo)(outer<inner1, inner2>&));

if try compile with:

myclass output; output << 3 << "hi";

then works fine, when try add std::endl

myclass output; output << 3 << "hi" << std::endl;  temp.cpp: in function 'int main()': temp.cpp:10: error: no match 'operator<<' in '((stream*)ss. stream::operator<< [with t = int](((const int&)((const int*)(&3)))))->stream::operator<< [with t = char [3]](((const char (&)[3])"hi")) << std::endl' /usr/include/c++/4.1.2/bits/ostream.tcc:657: note: candidates are: std::basic_ostream<_chart, _traits>& std::operator<<(std::basic_ostream<_chart, _traits>&, const _chart*) [with _chart = char, _traits = std::char_traits<char>] /usr/include/c++/4.1.2/bits/ostream.tcc:597: note:                 std::basic_ostream<_chart, _traits>& std::operator<<(std::basic_ostream<_chart, _traits>&, _chart) [with _chart = char, _traits = std::char_traits<char>]

i don't understand why in error printout there const int*. attempt learn more templates, trying cover more manipulators single piece of code.

edit sscce:

#include <fstream> #include <iostream>  class myclass : public std::ofstream { //class stream {     private:      public:          template<class t>         myclass& operator<<(const t& data_in) {             std::cout << data_in;             return *this;         }           template<             template<class, class> class outer_t,              class inner_t1,              class inner_t2             >         myclass& operator<<(outer_t<inner_t1, inner_t2>& (*foo)(outer_t<inner_t1, inner_t2>&)) {             return foo(*this);         }  };  int main() {     myclass output;     output << 3 << "hi";     output << 3 << "hi" << std::endl; }

don't try it. overloading of operator<< , operator>> iostream types complicated , messy.

what should instead create own std::streambuf subclass, , arrange standard stream class use that. way can override happens character stream data, without worrying overloaded operators, type conversion, formatting, , manipulators. example, see james kanze's filtering streambufs article, or boost library boost::iostreams.


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