nan

Simple Asynchronous Operations

This feature allows developers to perform asynchronous operations in their native addons. The code sample demonstrates how to create an asynchronous worker using 'NanAsyncWorker' and queue it with 'NanAsyncQueueWorker'.

const { NanAsyncWorker, NanAsyncQueueWorker } = require('nan');

class MyWorker extends NanAsyncWorker {
  constructor(callback) {
    super(callback);
  }
  Execute() {
    // perform heavy task
  }
  HandleOKCallback() {
    this->callback().Call(0, nullptr);
  }
}

NanAsyncQueueWorker(new MyWorker(new NanCallback(callback)));

Persistent References

This feature provides a way to create persistent references to V8 objects that won't be garbage collected until explicitly cleared. The code sample shows how to create, reset, check, and clear a persistent reference.

const { NanPersistent } = require('nan');

let persistent = new NanPersistent<v8::Object>();

persistent.Reset(obj); // obj is a V8 object
persistent.IsEmpty(); // checks if the persistent handle is empty
persistent.Clear(); // clears the persistent handle

Callbacks

This feature allows native module developers to store and invoke callbacks. The code sample illustrates how to create a 'NanCallback' from a V8 function and invoke it with no arguments.

const { NanCallback } = require('nan');

let callback = new NanCallback(info[0].As<v8::Function>());
callback.Call(0, nullptr);