[Javascript] return value from "ajax"/ function

[Brian L. Matthews]

>function requestFile(url)
>{
>httpRequest.open('get', url, true);
>httpRequest.onreadystatechange = function() { handleRequest() };
>httpRequest.send(null);
>}
>...
>var foo = requestFile(...);
>
>the handleRequest() function gets the data and when it's ready 
>loaded, and only then(!), requestFile() should return the data for 
>the var foo.
>
>how can I do this?!

You can't. The request runs asynchronously (the first 'A' in Ajax :-) 
). requestFile returns immediately (with undefined in your example), 
then at various stages in the request's lifetime, your handleRequest 
function will be called. When the request is complete, handleRequest 
should do whatever needs to be done with the response.

Brian