Uncaught SyntaxError: Unexpected token :

I am running an AJAX call in my MooTools script, this works fine in Firefox but in Chrome I am getting a Uncaught SyntaxError: Unexpected token : error, I cannot determine why. Commenting out code to determine where the bad code is yields nothing, I am thinking it may be a problem with the JSON being returned. Checking in the console I see the JSON returned is this:

{"votes":47,"totalvotes":90}

I don't see any problems with it, why would this error occur?

vote.each(function(e){
  e.set('send', {
    onRequest : function(){
      spinner.show();
    },
    onComplete : function(){
      spinner.hide();
    },
    onSuccess : function(resp){
      var j = JSON.decode(resp);
      if (!j) return false;
      var restaurant = e.getParent('.restaurant');
      restaurant.getElements('.votes')[0].set('html', j.votes + " vote(s)");
      $$('#restaurants .restaurant').pop().set('html', "Total Votes: " + j.totalvotes);
      buildRestaurantGraphs();
    }
  });

  e.addEvent('submit', function(e){
    e.stop();
    this.send();
  });
});

Solution 1:

Seeing red errors

Uncaught SyntaxError: Unexpected token <

in your Chrome developer's console tab is an indication of HTML in the response body.

What you're actually seeing is your browser's reaction to the unexpected top line <!DOCTYPE html> from the server.

Solution 2:

Just an FYI for people who might have the same problem -- I just had to make my server send back the JSON as application/json and the default jQuery handler worked fine.

Solution 3:

This has just happened to me, and the reason was none of the reasons above. I was using the jQuery command getJSON and adding callback=? to use JSONP (as I needed to go cross-domain), and returning the JSON code {"foo":"bar"} and getting the error.

This is because I should have included the callback data, something like jQuery17209314005577471107_1335958194322({"foo":"bar"})

Here is the PHP code I used to achieve this, which degrades if JSON (without a callback) is used:

$ret['foo'] = "bar";
finish();

function finish() {
    header("content-type:application/json");
    if ($_GET['callback']) {
        print $_GET['callback']."(";
    }
    print json_encode($GLOBALS['ret']);
    if ($_GET['callback']) {
        print ")";
    }
    exit; 
}

Hopefully that will help someone in the future.

Uncaught SyntaxError: Unexpected token :

Solution 1:

Solution 2:

Solution 3:

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