text: #include <nan.h>
  #include "graph.h"
  
  using namespace std;
  using namespace Nan;
  using namespace v8;
  
  NAN_METHOD(PassNumber) {
  
      Nan::Maybe<double> value = Nan::To<double>(info[0]); 
      Local<Number> retval = Nan::New(value.FromJust() + 42);
      info.GetReturnValue().Set(retval);   
  
  }
  
  NAN_METHOD(PassObject) {
      graph<string, int> G;
  
      G.addVertex("A");
      G.addVertex("B");
  
      info.GetReturnValue().Set(G);
  }
  
  NAN_MODULE_INIT(Init) {
     Nan::Set(target, New<String>("calc").ToLocalChecked(),
          GetFunction(New<FunctionTemplate>(PassNumber)).ToLocalChecked());
          
     Nan::Set(target, New<String>("buildGraph").ToLocalChecked(),
          GetFunction(New<FunctionTemplate>(PassObject)).ToLocalChecked());
  }
  
  NODE_MODULE(my_addon, Init)