General C++ Question

Ok, there are 2 things that have always confused me in C++:
1) If I have an object (say an instance of myClass) that I want to be global in all of my .cpp files, how do I do that?

2) How can I use an instance of class B in class A before the actual definition of B?
ie:

Code:

---

some .h file

class A {
private:
  B myB;
};
...
class B{
//definition of B
}

---

I am using Visual C++ 6

Thanks.

Quote:

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Originally posted by IncarnateRW
1) If I have an object (say an instance of myClass) that I want to be global in all of my .cpp files, how do I do that?

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Define that variable in all cpp files (with the same name of course). Make sure that all of them but one has the keyword extern in front.

Quote:

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2) How can I use an instance of class B in class A before the actual definition of B?

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I believe you could declare the class first, but I'm not 100% sure:

Code:

---

class B;

class A
{
  B MyInnerClass;
}

class B
{
  ...
}

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yes you can declare the an undefined class first...its just like a function prototype :)