Question

in my header file:

private:
struct movieNode {
    string title;

    castNode *castHead;

    movieNode *prev;
    movieNode *next;
};

struct castNode {
    string name;

    castNode *next;

};

movieNode *head;
movieNode *last;

but the compiler error is:

expected ‘;’ before ‘*’ token

my aim is that every movieNode should have a title and a cast list (with castNode).
thanks in advance.

Answer 1

movieNode needs to at least be able to see an incomplete type called castNode. At the moment, the compiler is going “Huh, castNode? What the hell is that?” because it hasn’t seen the definition of castNode yet. You can avoid it in this case by simply defining castNode before you define movieNode. Just swap the two structs around.

In other cases, where you have a cyclic dependency (if castNode had a pointer to a movieNode too, for example), you can use a forward declaration to provide an incomplete type (it would look like class castNode;) and then define it properly later.