Question

This code hangs.

I am reasonably sure it’s because the response in the anonymous function is a new variable not connected with the outer scope. How do I solve this?

function foo() { //...

    var url = "http://urliciously-urlish-url"
    response = null;
    $.get(url, function (data) {response = data;
                               });

    while( response === null)
    {
        1;
    }
    console.log(response);

    //...
}

Note I am aware that this design will (as usual for polling systems) hang the page until response becomes non-null. That’s OK in this context.

Answer 1

$.get is asynchronous. If you really want this to be synchronous, you’ll have to use the $.ajax function:

$.ajax({
    url: url,
    async: false,
    success: function(data) {
        response = data;
    }
});

That being said, I agree with cHao — you should get used to writing asynchronous code.