javascript - Multiple Inheritance in Node js with constructor set in parent class -

how can set constructor in parent class , call object in class inherited parent class.

parent class:

var request = resuire('request'); var = function(options) {    if(!(this instanceof a)) {      return new a(options);    }    var self = this;    self.id = math.random();    self.baseurl = 'http://example.com/';    self.options = options || {uri: self._baseurl}; }  a.prototype._request = function reqest(options, callback){    var self = this;    request(options, function(err, res, body){       self._determineresponse(err, res, body, function(){          return body;       }, callback);    } } 

child class:

var util = require('util'); var    = require('a'); var b = function(){     var self = this;   }  b.prototype.auth(username, password, callback) {    // access parent method (private or public) here perform request    a._request .... }  util.inherits(b, a); 

query:

• how set parent constructor
• best way access parent method