Difference between document.createElement('script') vs jQuery .getScript

Question

I've been having an issue getting .getScript to work in some odd cases.

For instance, this works to load the scripts only when needed.

function twitterSDK() {
    $jQ.getScript('http://platform.twitter.com/widgets.js');
}

function diggShare() {
    $jQ.getScript('http://widgets.digg.com/buttons.js');
}

function buzzShare() {
    $jQ.getScript('http://www.google.com/buzz/api/button.js');
}

However it doesn't seem to work on a few scripts that I wrote. If I call .getScript to fetch this JS file I've uploaded to Pastebin ( http://pastebin.com/GVFcMJ4P ) and call tweetStream(); nothing happens. However, if I do the following it works:

var twitter = document.createElement('script');
twitter.type = 'text/javascript';
twitter.async = true;
twitter.src = '/path-to/tweet.js';
$jQ('.twitter-section').append(twitter);
tweetStream();

What am I doing wrong? Any help would be awesome, thanks!

P.S. Which method is faster or more efficient?

Note: My code isn't hosted on pastebin, I just uploaded the contents of the .js file that is on my server to that site so it is easy to share. I am not leeching of pastebin for hosting ;)

Answer 1

jQuery's $jQ.getScript() is an asynchronous call. So if you were calling tweetStream() immediately after the getScript(), it would run before the script arrived.

You can call tweetStream() from (or as) a callback instead.

$jQ.getScript('/path-to/tweet.js', function() {
    tweetStream();
});

or this if you don't care about the value of this in tweetStream().

$jQ.getScript('/path-to/tweet.js', tweetStream);