How to produce

execute code below:

var xhr = $.get('some-resource');
setTimeout(function() {
    var i = 1;
    xhr.done(function() {
        alert(i);
    });
    var i = 2;
}, 500);

What is expected

Since $.get is processed asynchronously, the line var i = 2; should be executed before the alert, so it should alert ''2''

What is the result

If server responses within 500ms, it alerts ''1'', otherwise it alerts ''2''

Comment

This would cause confusion, the same code may emmit different result due to different network latency, so I recommend all callbacks registered to the jXHR object fires with a setTimeout to simulate the async nature of common XMLHttpRequest control flow.