Class ObjectWrap

nan_object_wrap.h:12–153

#define NAN_OBJECT_WRAP_H_

class ObjectWrap {
 public:
  ObjectWrap() {
    refs_ = 0;
  }


  virtual ~ObjectWrap() {
    if (persistent().IsEmpty()) {
      return;
    }

    persistent().ClearWeak();
    persistent().Reset();
  }


  template <class T>
  static inline T* Unwrap(v8::Local<v8::Object> object) {
    assert(!object.IsEmpty());
    assert(object->InternalFieldCount() > 0);
    // Cast to ObjectWrap before casting to T.  A direct cast from void
    // to T won't work right when T has more than one base class.
    void* ptr = GetInternalFieldPointer(object, 0);
    ObjectWrap* wrap = static_cast<ObjectWrap*>(ptr);
    return static_cast<T*>(wrap);
  }


  inline v8::Local<v8::Object> handle() const {
    return New(handle_);
  }


  inline Persistent<v8::Object>& persistent() {
    return handle_;
  }


 protected:
  inline void Wrap(v8::Local<v8::Object> object) {
    assert(persistent().IsEmpty());
    assert(object->InternalFieldCount() > 0);
    SetInternalFieldPointer(object, 0, this);
    persistent().Reset(object);
    MakeWeak();
  }

#if defined(V8_MAJOR_VERSION) && (V8_MAJOR_VERSION > 4 ||                      \
  (V8_MAJOR_VERSION == 4 && defined(V8_MINOR_VERSION) && V8_MINOR_VERSION >= 3))

  inline void MakeWeak() {
    persistent().v8::PersistentBase<v8::Object>::SetWeak(
        this, WeakCallback, v8::WeakCallbackType::kParameter);
#if NODE_MAJOR_VERSION < 10
    // FIXME(bnoordhuis) Probably superfluous in older Node.js versions too.
    persistent().MarkIndependent();
#endif