var object  = {
    a : 50,
    b: 60
}
var x = JSON.parse(JSON.stringify(object));
console.log(x);

// timer methods from web API 

setTimeout(function(){
    console.log('after 5 sec');
}, 5000);

var xhr = new XMLHttpRequest();
xhr.onreadystatechange =  function(){
    if(this.readyState == 4){
        clearTimeout(timeout);
    }
}
var timeout = setTimeout (function(){
     xhr.abort(); 
}, 2000);

xhr.open('GET', url, true);
xhr.send();
 
//----------------------------------------------//