gistfile1.txt

Make two file requests for two modules
----

This is the current state of our RequireJS usage. The map is automatically
generated by the BBC Mapper application. This is flexible and it works, however
it requires two downloads from the server.
    
    // map module ids to urls
    require({
        'swfobject-1':  'exact/path/1.2.3/swfobject.js',
        'jquery-1':     'exact/path/1.5.2/jquery.js'
    });
    
    // require module ids
    require(
        ['swfobject-1', 'jquery-1'],
        function(swfobject, $) {
            // callback in here
        }
    );


Change the map and make one file request for two modules
----

A niave approch to reducing the number of downloads from two to one. The
disadvantage is that it requires modifying (possibly overwriting) the URL values
in the map. In addition the size of the map bloats very quickly.

This works because on the server there is a process named "cat.php" that simply
joins the two files together into one. Care must be taken to keep the order
of the individual module URLs in the query string consistent, to allow caching
of the returned script.

    require({
        'swfobject-1':  'cat.php?exact/path/1.2.3/swfobject.js&exact/path/1.5.2/jquery.js',
        'jquery-1':     'cat.php?exact/path/1.2.3/swfobject.js&exact/path/1.5.2/jquery.js'
    });
    
    require(
        ['swfobject-1', 'jquery-1'],
        function(swfobject, $) {
            // callback in here
        }
    );


It's a plug in!
----

Here the map is left untouched, instead the package contents are specified via
a plugin. The advantage is that the map continues to work the same as always.
However, since require can only return one thing from a call to require a module
(or in this case a package of modules), we must change the parameters of our
callback to accept a single package, rather than two separate modules.

This works because, behind the scenes, our pkg! plugin consults the map and then 
converts the request for "swfobject-1+jquery-1" into a single require for 
the "cat.php?exact/path/1.2.3/swfobject.js&exact/path/1.5.2/jquery.js" URL. The
plugin follows a convention that guarantees the individual module URLs in the
querystring are always in the same order to allow caching of the returned script.

    require({
        'swfobject-1':  'exact/path/1.2.3/swfobject.js',
        'jquery-1':     'exact/path/1.5.2/jquery.js'
    });
    
    require(
        ['pkg!swfobject-1+jquery-1'],
        function(pkg) {
            // use pkg.swfobject
            // use pkg.jquery
        }
    );