User-defined Output Stream Manipulators in C

Question

I am learning C++, and in the part of user-defined output stream manipulatior, I am stuck. This is the example code:

    #include 
     using         


        

Answer 1

std::basic_ostream has several overloads of operator<<, one of which has the following signature:

basic_ostream& operator<<( basic_ostream& st, 
                       std::basic_ostream& (*func)(std::basic_ostream&) );

That is, this function takes a pointer to a function that both takes and returns std::ios_base. The method is called by this function and is incorporated into the input/output operation. Thereby making this possible:

std::cout << endLine;

So what will happen is that endLine is converted into a function pointer and a new line character will be written to the stream and afterwards a flush operation.