GeeWhiz Prolog - Part Zero - About the Project

Welcome

This is the first entry in a (planned) series of blog posts about creating an integrated development environment (IDE) for Prolog programming using the NetBeans IDE. The purpose of these blog entries is primarily to show how to create a functional editor, diagrammer and compiler wrapper for the Prolog programming language, and secondarily to explore some of the very cool features of the NetBeans IDE.

What's Prolog? What's NetBeans?

Right off the bat, I want to define my terms so you know if you ended up in the right place via your search engine:

NetBeans is a free, open-source IDE that does tons of cool stuff. It is for programmers. If you're not a programmer, you should probably quit reading this blog entry right now because you won't find it very interesting. If you are a programmer, you should consider using NetBeans, particularly if you are a Java coder or currently use Eclipse. NetBeans rocks.

Prolog is a programming language commonly used in artificial intellligence applications, natural language processing and expert systems. This blog won't really be addressing Prolog as a programming language per se, although I'll be talking about the language in passing as it pertains to the implementation of the IDE. The Prolog implementation I'll be using for this project is SWI Prolog, a free product that I respect tremendously. If you're going to work along with me as I build the GeeWhiz IDE, you might consider downloading it, although this is not a requirement.

Who Am Us, Anyway?

I should at this point confess that I'm not an expert with the NetBeans IDE, nor am I an expert Prolog programmer. I used to do a great deal of programming in Prolog, back in the days when Borland released Turbo Prolog, a successor to their very popular Turbo Pascal product. Ah, those were the days. Now I've forgotten most of what I knew about Prolog; this project resulted in part from my desire to reacquaint myself with the language. It also resulted from a desire to experiment with the new NetBeans version 6.1. Some very interesting things resulted from this experimentation, as you will see.

Why Prolog?

One of the nice things about using Prolog as a language around which to build an IDE is that the syntax is pretty simple and straightforward, relatively speaking. In absolute terms, however, parsing the language can present a few challenges, which we will gracefully surmount in later installments. Actually, the surmounting wasn't graceful at all, to tell you the truth. Much hacking and swearing and throwing of hamsters went on while I tried to figure the stuff out, but when I present it here, it should look as if I knew what the hell I was doing all along. Heh heh.

Is This A Tutorial? Can I Follow Along?

Hell yes, you should follow along, but this blog series won't really be a tutorial on NetBeans language implementation because I want this to be accessible to the experienced programmer who isn't all that familiar with the NetBeans IDE. I have discovered that much of the official NetBeans documentation assumes that you already know what the hell is going on under the hood. I certainly didn't know much about how the IDE works, at least when I started this project, so I thought I'd pass along what I learned as a help to others in my position. To that end, I will be discussing my own experiences more than should really be the case in a tutorial, including revealing (some of) the many mistakes I made in hacking this creature called GeeWhiz Prolog.

And yes, hacking is the right verb. I haven't studied (for example) the Visual stuff in NetBeans any more than I need to get GeeWhiz up and running. In other words, I know just enough to be dangerous. But if I had tried to become an expert, I'd still be studying months from now, and I have real work to do in the meantime. So I stand on the shoulders of giants (see tutorial references later) and only occasionally jump up and down on their heads. Even so, I think GeeWhiz came out pretty well. For hacking.

Isn't This Just A Rehash Of Other Tutorials?

I suppose in a way this is just a mashup of other information that's already out there. However, what I am bringing to the table is that I put all the information you need to start implementing a new language in NetBeans in one place. That be here, baby. If you don't believe me, do what I did and search NetBeans.org (and the rest of the Internet) for instructions on language support in NetBeans. Most of the pieces are there, but I haven't found anyplace where they are all assembled and integrated, especially in the form of the step-by-step how-to (or, sometimes, how-not-to) that I have tried to create here. You're welcome. See "donate" button.

What Do I Need To Create GeeWhiz Prolog Myself?

You should have an installed version of NetBeans 6.1, which you can get by following the link on the graphic above. You don't absolutely need SWI Prolog installed, but you should consider it as I mentioned above. You should also have had some experience in Java programming. While I am going to assume you know little about the NetBeans platform, I am going to bypass explaining a lot of the Java code I include. This is mostly because I imagine that you probably know more about Java than I do. I consider myself an intermediate-level Java programmer on a good day, and I haven't been having so many good days lately.

I Run On A Linux/Mac/(shudder)Windows Platform. Can I Construct GeeWhiz Prolog?

The platform I've been using to develop GeeWhiz is a creaky old Ubuntu Linux machine code-named Aspen. However, I'm happy to report that both NetBeans and SWI Prolog are multi-platform products. Windows users should be able to run the stuff you see in this GeeWhiz blog series just fine, and Mac users will probably be okay too. You should let me know if that isn't the case, just for future reference.

I Have A Comment...

Speaking of letting me know, I hope you'll pass along any comments you may have on the project. In fact, I'll be including a bunch of questions I have myself as we go, which perhaps some of you can answer.

What Features Does GeeWhiz Prolog Have?

Good question. Glad you're paying attention. When you're done with this series, you will have implemented an environment within NetBeans that includes:

• a text editor for Prolog source files that includes syntax highlighting and a sidebar navigator
• the ability to generate a visual and interactive map of Prolog predicate use
• in-place compilation of Prolog source (using SWI Prolog) with context-linked error and warning messages
• the ability to easily customize the IDE for use with other Prolog engines
• a framework upon which other language implementations can be constructed

Of course, another more subtle benefit of implementing GeeWhiz Prolog is that when you're done, you'll have a lot better understanding of how NetBeans works. This is non-trivial if you're interested in using NetBeans as an IDE for your own language, believe me.

Why Did You Name It GeeWhiz Prolog?

I called this project "GeeWhiz" because I began it to see what nifty things I could do with NetBeans. Sure, I needed an editor for Prolog source code, but hey, I could have used Emacs and went along my merry way (although I hate Emacs, btw). So this became a "geewhiz" application: "Gee whiz, I didn't know I could do that with NetBeans!" "Gee whiz, this is so cool!" etc. etc. So bear with me -- you'll see.

Will You Include Another Paragraph With Screenshots In This Entry?

Sure I will. I am going to stick in a sample screenshot or two here because I am new to the this blogging vehicle, Supersized, and I want to see what they look like.

I make a lot of use of screenshots, and I want to make sure they come out okay. My current plan is to include them as thumbnails, because most of the screenshots

are c. 1024 x 768 pixels and aren't really amenable to being included in the body of the blog post as full-size images. Thumbnails, if you don't know, can be clicked to view the full-size image. This is a big help since you'll hit your forehead on your monitor trying to read the text in the thumbnails. Trust me.