var poller = {    // number of failed requests   failed: 0,    // starting interval - 5 seconds   interval: 5000,    // kicks off the setTimeout   init: function(){       setTimeout(           $.proxy(this.getData, this), // ensures 'this' is the poller obj inside getData, not the window object           this.interval       );   },    // get AJAX data + respond to it   getData: function(){       var self = this;        $.ajax({           url: 'foo.htm',           success: function( response ){                // what you consider valid is totally up to you               if( response === "failure" ){                   self.errorHandler();               } else {                   // recurse on success                   self.init();               }           },            // 'this' inside the handler won't be this poller object           // unless we proxy it.  you could also set the 'context'           // property of $.ajax.           error: $.proxy(self.errorHandler, self)       });   },    // handle errors   errorHandler: function(){       if( ++this.failed < 10 ){            // give the server some breathing room by           // increasing the interval          this.interval += 1000;           // recurse          this.init();       }   }}; // kick this thing offpoller.init();

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