Q:

|| (OR operator) in JavaScript when creating jQuery plugin

Maybe I'm just too tired at the moment, but I can't find the reason why a plugin developer used the following construction:
jQuery.<myPlugin> || (function($)) {

    var $.<myPlugin> = {

        // plugin code goes here...

    }

})(jQuery);

Of course this is a common construction, except for the use of || (OR operator as far as I know), which I don't understand.
Can you tell me why the developer used ||?

A:

It would first check if jQuery.<myPlugin> exists, if not, it will continue to build the function.

