Server Scriptlets are the most recent evolution of scripting technology. They bring to light two key topics that will play a pivotal role in Web technology in the months to come—scriptlets and XML. Scriptlets are reusable objects made up of script code. XML is an HTML-like syntax that allows you to describe virtually any kind of complex data structure with a natural and greatly expressive language. By combining scriptlets and XML we have a new file format that can be exploited to define a high-level interface for a COM object.
Server Scriptlets are just this. Pieces of script code with a layer of information which is interpreted at run-time by a specialized module. This run-time library shields the details of the script code and exposes to the external world a table of functions through the usual COM conventions.
From within Visual Basic applications (and not only them) you can now call a piece of script code using the same COM approach you're already familiar with. This is the first step towards the time when you can use a script language to implement any COM interface. But there's another equally impressive feature—the possibility to write your own generic COM servers with script code. This feature is still to come. Today, at least, we can't yet define a totally new COM interface.
The current beta version of the Server Scriptlet Package allows us only to implement COM interfaces for which exists a run-time module (called interface handler) that provides the COM-based interaction with clients. Overall, the implementation is far from being complete but it looks really superb so far!
In this chapter, we provided an overview of the Server Scriptlet technology paying particular attention to a comparison between Server Scriptlets and DHTML Scriptlets (the main focus of this book). In particular, we covered:
Server Scriptlets are a comprehensive technology that encompass DHTML Scriptlets—in our opinion they will continue living side-by-side at least for the next few months, maybe for the next couple of years. However, none of us have magical powers (as far as I'm aware) and software is a very hard field to forecast.