On Tue, Oct 9, 2018 at 11:45 AM Mike Moening <mike.moen...@gmail.com> wrote:
> With recent versions of v8 the SetWeak method has changed and the > Persistent<Value>* parameter has been dropped from the destructor callback. > The destructor callback function is **supposed** to Reset() the persistent > or its a leak. > If you don't V8 crashes and tells you this: > > Check failed: Handle not reset in first callback. See comments on > |v8::WeakCallbackInfo > > Old signature: > void MyClass::DestructorCallback(Isolate* pIsolate, Persistent<Value>* > value, MyClass* pObj) > > New signature > void MyClass::DestructorCallback(const WeakCallbackInfo<MyClass>& oValue) > > If I call it like this: > Persistent<Object> obj(isolate, objLocal); > obj.SetWeak<MyClass>(pMyObject, MyClass::DestructorCallback, > WeakCallbackType::kParameter); > > How can I pass the Persistent into my DestructorCallback function so I can > Reset it?? > Persistent cannot be copied. > So how can I Reset() it in the callback? > Any help would be great. > See this example: https://cs.chromium.org/chromium/src/v8/src/d8.cc?l=2312&gsn=SetWeak You can often find such hints in the V8 API Changes doc <https://docs.google.com/document/d/1g8JFi8T_oAE_7uAri7Njtig7fKaPDfotU6huOa1alds/edit> (just ask your favorite search engine for "V8 API Changes" to find it). > Also the WeakCallbackType::kParameter vs WeakCallbackType::kFinalizer > thing has me confuzeled too. > Which is the right type to use? > See the documentation: // kParameter will pass a void* parameter back to the callback, > kInternalFields > // will pass the first two internal fields back to the callback, kFinalizer > // will pass a void* parameter back, but is invoked before the object is > // actually collected, so it can be resurrected. In the last case, it is > not > // possible to request a second pass callback. > enum class WeakCallbackType { kParameter, kInternalFields, kFinalizer }; Does that help? > > Thanks! > > -- > -- > v8-users mailing list > v8-users@googlegroups.com > http://groups.google.com/group/v8-users > --- > You received this message because you are subscribed to the Google Groups > "v8-users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to v8-users+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > -- -- v8-users mailing list v8-users@googlegroups.com http://groups.google.com/group/v8-users --- You received this message because you are subscribed to the Google Groups "v8-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to v8-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
