Question about string

[newguyhere]

So i was trying to print hello world on screen using oop
Here is my header

virtual void Hello(std::string str);


and here is the definition

void Base::Hello(std::string str) {

	std::cout << "hello " << str << "\n"; // this gets an error
}

But for some reason I kept having this error

no operator "<<" matches these operands
            operand types are: std::basic_ostream<char, std::char_traits<char>> << std::string

But if I put & on the str
std::cout << "hello " << &str << "\n";

It is working fine.
I dont get it. Why is that?
The str is pass by value. I should not have to dereference it

int main() {

	BaseClass b;
	b.Load("hello");

	return 0;
}

are all string in c++ a pointer?
also I never declare any pointer on string. (string*)

[LB]

Did you remember to #include <string> ?

[newguyhere]

Yeah I did. Its already on my header file. Im still confuse about the & part though.

[LB]

What compiler are you using and which standard of C++ are you targeting?

[newguyhere]

I think Visual studio compiler? I am using VS2015.

Im not really sure about the standard c++ question.

[LB]

I'm also using Visual Studio 2015, and I don't have that issue. Try uninstalling and reinstalling (sorry, I know it takes forever to install).

[JLBorges]

If pre-compiled headers are being used, turn them off:
Project => Properties => C/C++ => PreCompiled Headers => Not Using Precompiled Headers

The do a clean rebuild. Build => Rebuild