No worries on being pedantic, Alex. If I'd been working 24 hours straight,
I'd be worried I might understand a critical detail too.
Yes, I do mean to have you concatenate all of jquery.js along with the
plugin and your code into a single large .js file, and have your loader.js
create a dynamic script element to load that single file (or a
packed/minified/gzipped version of it).
No, it won't cause you any problems to concatenate jquery.js along with your
other files. There's nothing special about jquery.js; it's just a .js file
like any other.
There is one problem you can run into when you concatenate files. If one
source file has a missing semicolon at the very end, then when you append
another file, the JS interpreter may combine statements in a way you didn't
intend.
This shouldn't be a problem for jquery.js and a typical plugin, but it you
want to be absolutely sure, simply add a ; between each source file. You can
make that part of a separator line if you want, perhaps like this:
;//--------------------------------------------------------
jquery.js goes here
;//--------------------------------------------------------
Plugin goes here
;//--------------------------------------------------------
Your script goes here
;//--------------------------------------------------------
That way you get a nice visual separation between the scripts, and the extra
semicolons won't hurt anything.
-Mike
> From: Alex Weber
> Sent: Tuesday, September 02, 2008 2:07 PM
> To: jQuery (English)
> Subject: [jQuery] Re: best techniques to optimize loading of
> multiple libraries?
>
>
> Thanks again Mike!
>
> I reckon I have it down to a 'T' now! :)
>
> Just one doubt (sorry i've taken so much of your time already!):
>
> When you say:
> "Concatenate all of your scripts into a single file."
>
> Do you mean the entire jquery library as well?
>
> Is this feasible? Like, copy and paste the entire jquery
> library (uncompressed), one plugin, and my custom code into
> one huge .js file and then pack or minify it?
> And host it somewhere fast like cachefly?
>
> I can see doing this for the plugin and my custom js but
> jquery also seems asking for trouble no?
>
> Or am i not getting it? Did you mean dynamically append "loader.js"
> in the main document body, and then in loader.js have 3
> separate <script src>? (wait does that even work?) sorry its
> late here ive been on a crazy reching on 24 hour work bender.... :S
>
> Thanks again and sorry for being so pedantic!!
>
> Alex
>
> On Sep 2, 4:40 pm, "Michael Geary" <[EMAIL PROTECTED]> wrote:
> > > From: Alex Weber
> >
> > > So just to clear things up, you prefer using document.write() to
> > > insert <script> tags instead of appending the elements to the DOM:
> >
> > > var finan = document.createElement('script');
> > > finan.type = 'text/javascript';
> > > finan.src =
> > > 'http://www.mydomain.com/js/mts_finan.js';
> > > head.appendChild(finan);
> >
> > > i guess its more efficient because you don't have to access the
> > > document object, but any other particular reasons?
> >
> > No, that isn't the reason at all. It's because it makes the
> code much
> > simpler. You don't have to write any code to load the
> scripts in their
> > proper sequence; it happens automatically. <script> tags
> are evaluated
> > in the order they appear in the source code, and code you add with
> > document.write is inserted immediately after the end of the
> script tag
> > that does the document.write.
> >
> > Dynamically inserting a script element with
> createElement/appendChild
> > is a great technique - in fact it's the basis for the popular JSONP
> > method of cross-domain JSON downloads - but it doesn't
> automatically
> > tell you when the script is loaded. That why your developer
> wrote that
> > repeating interval code
> > - to check when each script is ready and load the next one
> in sequence.
> >
> > > Awesome, one huge problem out of the way!
> >
> > Well, maybe, maybe not... :-) See below...
> >
> > > We're currently at a point where our server isn't exactly being
> > > overloaded so i think its safe to host jquery.min on
> google code and
> > > the plugin (yet to be minified) and custom code possibly
> combined in
> > > 1 file, since there won't be a lot of custom code to begin with.
> >
> > > Also, to satisfy your curiosity, the whole purpose of using the
> > > mts_load.js function is because this code is a part of a banner
> > > we're planning to distribute and host in numerous
> websites, so a lot
> > > of them won't want scripts other than their own embedded
> directly,
> > > so we found that calling one simple function (mts_load)
> that would
> > > to all the dirty work was acceptable with them :)
> >
> > When I recommended document.write, I wasn't really thinking
> about the
> > whole context. There may be one good reason to use the
> dynamic script
> > elements instead. When you document.write the script tags,
> the browser
> > will wait while those script files are loaded. If you use dynamic
> > script elements, the browser continues loading the rest of the page
> > while the additional scripts are loaded. The only script it
> waits for
> > is the main loader script which is loaded with a script tag.
> >
> > If this behavior is what you want, then you can still get
> it without
> > all the timers and extra complication. Concatenate all of
> your scripts
> > (except the loader itself) into a single file. Then simply use a
> > single dynamic script element to load that entire script. You don't
> > need any timers or sequencing that way. Simply load that one big
> > script, and the code in it will run in the order you expect. Very
> > simple, and you still get the benefit of letting the page continue
> > loading while the secondary scripts are fetched asynchronously.
> >
> > -Mike
>
