Storing a JavaScript constructor for later use

Question

I'm writing a node.js (0.12) library consisting of 50% Pure JavaScript classes and 50% Pure C++ classes. Certain functions in the C++ classes need to return instances of the JavaScript classes. I figure I need to store the constructors of the JavaScript classes in

Persistent<Function>

s. Assuming I can get the constructors as arguments how can I store them for later

NewInstance()

ing.

JS

function MyType()

{

    this.a = 0; 

};



native.store (MyType)

C++

void Wrapper::store (const FunctionCallbackInfo<Value>& args)

{

    // Need to store args[0] as MyTypeConstructor for later

}



void Wrapper::use (const FunctionCallbackInfo<Value>& args)

{

    Isolate* isolate = Isolate::GetCurrent();

    HandleScope scope (isolate);



    auto ctor = Local<Function>::New

        (isolate, MyTypeConstructor);



    ctor->NewInstance();

}

Recommended for you: Get network issues from WhatsUp Gold. Not end users.

Answer 1

I think I found the answer. Just like in the example under MyObject::Init you can use the Reset function to bind a local function to a persistent function.

Persistent<Function> MyTypeConstructor;

void Wrapper::store (const FunctionCallbackInfo<Value>& args)
{
    Isolate* isolate = Isolate::GetCurrent();
    HandleScope scope (isolate);

    auto ctor = Local<Function>::Cast (args[0]);
    MyTypeConstructor.Reset (isolate, ctor);
}

Storing a JavaScript constructor for later use

Sign up