gorillajs/app/plugins/extra_packages/node_modules/nan/doc/callback.md

A smart development environment designed to easily install and neatly manage web applications. Gorilla JS frees you from the repetitive daily tasks like apps installation, database management, creation of virtual environment, server configuration… And it

## Nan::Callback

`Nan::Callback` makes it easier to use `v8::Function` handles as callbacks. A class that wraps a `v8::Function` handle, protecting it from garbage collection and making it particularly useful for storage and use across asynchronous execution.

 - <a href="#api_nan_callback"><b><code>Nan::Callback</code></b></a>

<a name="api_nan_callback"></a>
### Nan::Callback

```c++
class Callback {
 public:
  Callback();

  explicit Callback(const v8::Local<v8::Function> &fn);

  ~Callback();

  bool operator==(const Callback &other) const;

  bool operator!=(const Callback &other) const;

  v8::Local<v8::Function> operator*() const;

  v8::Local<v8::Value> operator()(v8::Local<v8::Object> target,
                                  int argc = 0,
                                  v8::Local<v8::Value> argv[] = 0) const;

  v8::Local<v8::Value> operator()(int argc = 0,
                                  v8::Local<v8::Value> argv[] = 0) const;

  void SetFunction(const v8::Local<v8::Function> &fn);

  v8::Local<v8::Function> GetFunction() const;

  bool IsEmpty() const;

  v8::Local<v8::Value> Call(v8::Local<v8::Object> target,
                            int argc,
                            v8::Local<v8::Value> argv[]) const;

  v8::Local<v8::Value> Call(int argc, v8::Local<v8::Value> argv[]) const;
};
```

Example usage:

```c++
v8::Local<v8::Function> function;
Nan::Callback callback(function);
callback.Call(0, 0);
```