How loop std::ostream and std::istream?

[iQChange]

I was reading the book C++: How to program (Deitel, 6th Edition), and on the page 602 I implement my own String (training). But I want to implement my own StringStream. So, how can I make a loop like stringstream, and accept all kind of data?
E.G

double PI = 3.14;
std::stringstream a;
a << "The value of PI with precision 2 is " << PI; 

Should I use templates? How do std::ostream loops work?
Thanks!

[LB]

http://www.cplusplus.com/reference/ostream/ostream/operator%3C%3C/
http://en.cppreference.com/w/cpp/io/basic_ostream/operator_ltlt

There are no 'loops' involved.

[iQChange]

Anyway, how can I make one stringstream (just the operators << and >>)?

[ajh32]

When you say:

Anyway, how can I make one stringstream (just the operators << and >>)?

Do you mean, in your own class?

[iQChange]

When you say:

Anyway, how can I make one stringstream (just the operators << and >>)?


Do you mean, in your own class?

Yes.

[ajh32]

How about this:

class MyClass
{
public:
	
   ...

   friend std::ostream& operator << (std::ostream& os, const MyClass& obj)
   {
      os << obj.var;
      return os;
   }

   ...

private:
   int var;
};

[iQChange]

@ajh32 Stringstreams just get the value from any numerical \ char variable and put it on a private char*. That's the challenge;

[LB]

I'm pretty sure that stringstreams use a std::string internally in modern implementations.