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Object Problem...(newbie stuff)...

Afternoon all...

Im trying to create a class like such:

class Node{
...
Root *root;
...
}

class Root{
...
Node *node;//actually a vector, but none the less..
...
}

The compiler wont let me place a pointer to root into my node object because root hasnt been declared yet...and if I switch the order the problem will be just the opposite. Is this an impossiblity w/ C++? (I'm an experience Java programmer, new to c/c++).

Thanks!
-hhb

ASKER CERTIFIED SOLUTION

Kent Olsen

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Kent Olsen

One of the things about C, C++, PASCAL and a lot of other languages is that you can only create references to objects that the compiler knows about. (Personally, I'd prefer that the compiler resolves some of this later. After all, a pointer to a class takes up exactly the same space as a pointer to an int so it's not a matter of the type of object being indefinite.)

But I digress.

For complex types (struct, typedef struct, and class) it is often desireable to have links in both directions. But as you've discovered, the compiler won't let you define have a pointer to an object for which it has no definition.

Hence, the forward reference.

class Second;

class First
{
Second *SecondPtr;
};

class Second
{
First *FirstPtr;
}

Good Luck,
Kent

hbean

ASKER

Awesome. I knew it was easy LOL. Thanks!