create_a_clock.js

function my_Clock() 
  {
  this.cur_date = new Date();
  this.hours = this.cur_date.getHours();
  this.minutes = this.cur_date.getMinutes();
  this.seconds = this.cur_date.getSeconds();
  }
my_Clock.prototype.run = function ()
  {
  setInterval(this.update.bind(this), 1000);
  };
my_Clock.prototype.update = function () 
  {
  this.updateTime(1);
  console.log(this.hours + ":" + this.minutes + ":" + this.seconds);
  };
my_Clock.prototype.updateTime = function (secs) 
  {
  this.seconds+= secs;
 if (this.seconds >= 60)
  {
  this.minutes++;
  this.seconds= 0;
  }
 if (this.minutes >= 60)
  {
  this.hours++;
  this.minutes=0;
  }
if (this.hours >= 24)
  {
  this.hours = 0;
  }
};
var clock = new my_Clock();
  clock.run();