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DSL tools available

  • Artikel

In my previous job, I used to go around showing people some rather neat techniques for doing requirements analysis (and in particular the Catalysis method I created with Desmond D'Souza). One of the big frustrations was that we didn't have any tools to support our methods -- always the most difficult thing that clients would ask about.

Well, now I'm building tools, and the first sampler of our technology can be downloaded today. The toolkit will support the development and application of domain-specific languages in your project. At https://lab.msdn.microsoft.com/vs2005/teamsystem/workshop/dsltools/, you can get a preview of part of the kit, our metamodel (= abstract syntax) editor. It isn't the complete kit, and most of what you see will change; but from it, you can get some idea of where we're headed. In a couple of months, you will be able to download enough bits to create and use a basic graphical DSL.

Let's suppose your company develops software that operates the bag-handling systems in airports. Hitherto, you handled each new airport project by adapting the software you wrote for past projects. Now with our toolkit, you will be able to:

  • Define the 'object model' ( = abstract syntax or metamodel) of your language -- that is, the concepts and relationships you want to handle in it. In our example, you might create a language about the configuration of check-in desks, conveyor belts and loading bins in airports -- these are the things that vary from one project to the next.
  • Define a graphical concrete syntax for the language -- the boxes, lines, etc that represent the concepts on-screen -- e.g. diagrams containing things that look like checkin desks, belts, etc.
  • Create, at a mouse-click, a graphical editor for your language, that your colleagues will use to design a specific airport.
  • Develop code generators that will create software, configuration files, reports and other artefacts from the graphical model. That is, the software that runs the bag-handling equipment, the user interface for the operators, as well as lists of hardware parts.  This is the most application-specific part of the job, and depends heavily on a framework developed -- and that continues to develop -- from your existing software.

The preview you can get from our website now demonstrates an editor for the first part, the object model. It is in itself a domain-specifc language, created specifically for this purpose. It has similarities to UML class diagrams, but the layout is specifically targeted at the tree-like structure of language definition. (You might recall BNF?)

The toolkit for all of the above steps will be available shortly: we demonstrated it on the MS stand at OOPSLA, and want to make it a bit more robust before publication.

The great benefit of a DSL is that once you've got it (and the framework the generated code runs atop), developing new applications is a much more agile process than before. The DSL can focus almost entirely on the requirements of each problem: the implementation patterns for the domain are encapsulated in your framework; so that it's possible to adopt a process like eXtreme Programming, even for large sophisticated projects.  (The same is true to some extent of any software-product-line method; DSLs have the advantage that you're working in a syntax close to what people in the domain understand, rather than coupling pieces of code or composing in XML.)

This doesn't mean that we can throw away our other software development tools and processes of course: building the framework that implements the DSL isn't usually just trivial. But we think that choosing a DSL as the top layer of an architecture makes the whole project more agile.

Comments

  • Anonymous
    November 08, 2004
    I think it's exciting that MS is doing all this DSL work, and pushing SW-Dev forward.

    While designing the tools and technology, I hope you keep in mind that DSLs will be combined into systems of DSLs. An example might be a robot in which one DSL is used for limb movements (concerned with forces, positions, and physical contraints), while another DSL might be used for a planning system (concerned with decomposing a task into primitive movements).

    I'm concernd about DSLs growing and changing over time, and the operations on whole DSLs needed to support this: merging, splitting, composing, evolving, upgrading, etc.
  • Anonymous
    November 08, 2004
    Yes, model composition and evolution is very much in our sights -- it's a nice interesting problem! Especially the bits about migrating existing language statements to newer versions of your language.
  • Anonymous
    November 11, 2004
    I'd be interested to know how your tools differ from doing the following:

    - creating a bunch of stereotypes in a UML tool (possibly with some icons to make it look prettier). So for baggage handling I could build various domain specific stereotypes: conveyor belts, etc.
    - define some code mappings into a target language that generate code for specific stereotype instances
    - start modelling!


  • Anonymous
    November 11, 2004
    I think the idea of refining a software system by refining the models step by step is very appealing. If you look at multiple viwpoints one will have to deal with the synchronization between the models. As Jack Greenfield mentioned in his presentation at OOPSLA, there might be many models and keeping them all up to date with the provided meta data seems to be a big task.
    We are currently working on a simple protoype to show these mappings between models and it does not seem to be trivial. I am looking forward to see moree of the promised tool support from Microsoft.
    So Long
  • Anonymous
    November 11, 2004
    I'd be interested to hear more about your prototype -- model composition is a particular interest.

    Alan
  • Anonymous
    November 15, 2004
    Alan,

    Took a look at the walkthrough and I must say, while was interesting, it is a bit hard to see the forrest by looking at this single tree. The walkthrough was OK with what to do, but a bit light on the "whys" and how it fits into the bigger picture.

    I look forward to seeing more of the tools so I can have a "greater" experience.

    bill
  • Anonymous
    November 16, 2004
    Yes, it's sometimes had the same effect on me!

    What's visible in the walkthrough is just a grammar editor. Not huge in its own right, but a step in what we think is the right direction.

    Alan