Question

I’m trying to overload the == operator to compare between two objects. For some reason the overloaded handler is never called.

class gxCallback
{
public:
    virtual bool operator==(const gxCallback &aOther) const
    {
        // This is never called
        return true;
    } 
};

typedef std::vector < gxCallback* > CallbackList;

void gxObservable::Fire( gxCallback *aCallback )
{
    CallbackList::iterator iCallback;

    for ( iCallback = mCallbacks.begin(); iCallback != mCallbacks.end(); ++iCallback )
    {
        if ( aCallback == *iCallback ) // The comparison is never made via the overloaded ==
        {
            // Do something
        }
    }  
}

Answer 1

You’re calling it on a pointer, not the object. You’ll have to compare the object with the one the iterator is referencing:

if (*aCallback == **iCallback)

You also have to make sure the “pointers” hold something before you dereference them.