c++ - How to pass multi string with "<<" operator without using Macro preprocessor -

in order support logging string << operator, used macro handle it.

my_log_fun("hello"<<"world")  //in real case, people can pass variables 

and macro like

#define my_log_fun(out)  \     ostringstream os; \    os << out; \    play_with(os) \ 

while macros give limitation continues task, there way make my_log_fun in real function can receive parameter "hello"<<msg<<"world"?

"is there way make my_log_fun in real function can receive parameter << "hello"<<msg<<"world"?"

yes there is. instead of using macro, i'd recommend use class , overloaded global operator specialized this:

class mylogger { public:     mylogger(std::ostream& logstream)      : logstream_(logstream)     {}      template<typename t>     friend mylogger& operator<<(mylogger&, const t&); private:     std::ostream&  logstream_; };  template<typename t> mylogger& operator<<(mylogger& log, const t& value) {     log.logstream_ << value;     return log; } 

and use it:

int main() {     mylogger log(std::cout);      log << "hello" << " world!";  }  

see working demo.

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_{note:
you'll need write/delegate own stream i/o manipulator functors (like e.g. std::endl) them working mylogger& operator<<(mylogger&, t) operator overload.}