using setTimeout on promise chain : <p>Here i am trying to wrap my head around promises.Here on first request i fetch a set of links.and on next request i fetch the content of first link.But i want to make a delay before returning next promise object.So i use setTimeout on it.But it gives me the following JSON error (<strong><code>without setTimeout() it works just fine</code></strong>)</p>

<blockquote>
  <p>SyntaxError: JSON.parse: unexpected character at line 1 column 1 of
  the JSON data</p>
</blockquote>

<p><strong><em>i would like to know why it fails?</em></strong></p>

<pre><code>let globalObj={};
function getLinks(url){
    return new Promise(function(resolve,reject){

       let http = new XMLHttpRequest();
       http.onreadystatechange = function(){
            if(http.readyState == 4){
              if(http.status == 200){
                resolve(http.response);
              }else{
                reject(new Error());
              }
            }           
       }
       http.open("GET",url,true);
       http.send();
    });
}

getLinks('links.txt').then(function(links){
    let all_links = (JSON.parse(links));
    globalObj=all_links;

    return getLinks(globalObj["one"]+".txt");

}).then(function(topic){


    writeToBody(topic);
    setTimeout(function(){
         return getLinks(globalObj["two"]+".txt"); // without setTimeout it works fine 
         },1000);
});
</code></pre>
