endl of C++

C++ have some manipulators : setw(int w), setprecision (int d), setiosflags (long f) resetiosflags (long f), endl ...

the manipulator is just function. Did you know that?? ( I didn't know that.)

In my case, I used endl unconsciously. (별생각없이를 적고 싶은데....내일 찾아보자.)

cout which it use for display on screen, is object of ostream.

cout << "Hello, world";
cout << endl;

Above statement can change below statement.

cout.operator<< ("Hello, world");
cout.operator<< (endl);

that means << operator overloading.

ostream& operator<< (ostream& (*fn) (ostream &) );
{
      return (*fn)(*this);
}

Did you see that? The argument is function pointer!!!!!!

endl is function. endl function is below.

ostream& endl (ostream &stream)
{
stream << "\n";
return stream;
}

In conclusion,

cout << endl;

1.

cout.operator<< (endl);

2.

operator<< ( ostream& (*fn) (ostream& stream) )
{
return (*fn)(*this);//*fn --> endl
}

3.

ostream& endl (ostream &stream)
{
stream << "\n";
return stream;
}

That is endl internal operation.

I'm sorry. my english is not good.

Please, understand this.

In my case, this operation is really fun and interesting.

Thanks^^