## Scopes A _local handle_ is a pointer to an object. All V8 objects are accessed using handles, they are necessary because of the way the V8 garbage collector works. A handle scope can be thought of as a container for any number of handles. When you've finished with your handles, instead of deleting each one individually you can simply delete their scope. The creation of `HandleScope` objects is different across the supported versions of V8. Therefore, NAN provides its own implementations that can be used safely across these. - Nan::HandleScope - Nan::EscapableHandleScope Also see the V8 Embedders Guide section on [Handles and Garbage Collection](https://github.com/v8/v8/wiki/Embedder%27s%20Guide#handles-and-garbage-collection). ### Nan::HandleScope A simple wrapper around [`v8::HandleScope`](https://v8docs.nodesource.com/io.js-3.3/d3/d95/classv8_1_1_handle_scope.html). Definition: ```c++ class Nan::HandleScope { public: Nan::HandleScope(); static int NumberOfHandles(); }; ``` Allocate a new `Nan::HandleScope` whenever you are creating new V8 JavaScript objects. Note that an implicit `HandleScope` is created for you on JavaScript-accessible methods so you do not need to insert one yourself. Example: ```c++ // new object is created, it needs a new scope: void Pointless() { Nan::HandleScope scope; v8::Local obj = Nan::New(); } // JavaScript-accessible method already has a HandleScope NAN_METHOD(Pointless2) { v8::Local obj = Nan::New(); } ``` ### Nan::EscapableHandleScope Similar to [`Nan::HandleScope`](#api_nan_handle_scope) but should be used in cases where a function needs to return a V8 JavaScript type that has been created within it. Definition: ```c++ class Nan::EscapableHandleScope { public: Nan::EscapableHandleScope(); static int NumberOfHandles(); template v8::Local Escape(v8::Local value); } ``` Use `Escape(value)` to return the object. Example: ```c++ v8::Local EmptyObj() { Nan::EscapableHandleScope scope; v8::Local obj = Nan::New(); return scope.Escape(obj); } ```