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I could have sworn this is a dupe of a story about Tim Hartnell's book, but a cursory search isn't turning up anything. Maybe it was on ArsTechnica...

I could have sworn this is a dupe of a story about Tim Hartnell's book, but a cursory search isn't turning up anything. Maybe it was on ArsTechnica...

Here you go -- Inform supports PalmOS.

So obviously, we should write everything in Z-code, which runs on possibly the most portable virtual machine ever created.

It reminds me a lot of the programming languages used for creating "interactive fiction" or "text adventure" games. Specifically Inform and TADS.

Game and simulation programming lends itself perfectly to aspect oriented design because it's full of objects and events which must be responded to. For example a "banana" object might have a "before eating" action which checks that the banana has been peeled and an "after eating" action in which it removes itself from the player's possessions and places a "banana peel" object there instead. A "monkey" object, might have an "after player enters room" action in which it attempts to steal the banana from the player. Since there are an unlimited number of possible events, it is impractical have a virtual function for each of them, so aspect-oriented programming is the only viable solution (especially if you want to create extensible libraries).

People have written object-oriented world-simulation languages, just not in exactly the way you describe; they're languages designed for writing "interactive fiction", and the two best known are Inform and TADS (with Inform being my personal preference; kind of like C, only comprehensible and with a free Designer's Manual available for download).

The only problem is, even with these, it's very very hard to write a consistent and bug-free model of the world, simply because there are so many states for a text adventure game to get itself into. Then you have players who do crazy things in them, deliberately looking for bugs. Still, they're very flexible and it can be a lot of fun to use them.

Inform (and its standard libraries) is currently on something like release 6.10, so it's very stable and likely won't be changed at all in the coming years. TADS is currently on version 2, but work on TADS 3 is advancing well.

For Zork purists, RTZ was only so-so. Infocom was really Activision by that point, and most of the original "implementors" were gone.

However, before you launch into making your own parser, you might want to do a little surfing. The 'interactive fiction' community is still alive and writing games in the old-style. I'd recommend taking a look at Inform to start, but then again, I'm a little biased.

There just happens to be a boatload of example code for teaching that uses various primitive forms of BASIC.

My 11-year-old son found a book at the school library on programming adventure games that even DOS QBASIC was a bit too advanced for (QBASIC doesn't sort numbered statements). Ah, here it is: "How to Create Adventure Games" by Cristopher Lampton (long out of print). An excellent intro to programming, and a more fun result than many of the simpler programming tutorials.

For that matter, Inform would be great to have around at the middle-school level. It's got OO, it's got structure, sure it's got no techniques that can be applied to other software engineering, but the effort/fun ration is about as good as you can get.

My other son is a freshman in high school taking C++, and the students are all bummed they're not writing games. With Inform, you're gaming in a day or so.

And if you want to get really geeky, go ahead and pick up a copy of Inform -- an IF authoring system. (IMHO, Inform is the *best* system, but that's open to debate...)

He *is* programming. Inform is an OO programming language for creating Zmachine text-adventure games -- like the old Infocom games.

Check out the Inform website.

Then what you want isn't Neverwinter Nights -- it's Inform, which lets you do precisely that. And it's free, and it's available for just about any OS you might possibly name (including Linux).

But sadly, this framework is almost completely incompatible - almost by definition - with Baldur's Gate-style graphics.

Not necessarily -- Version 6 of the Z-Machine, HTML TADS, and Glulx all allow graphics and sound. The problem, I think, is that designers of many graphical multimedia games worry too much about pretty pictures and sound, and not enough about good plot, good characters, good writing, et cetera. It's getting better, though.

See rec.arts.int-fiction for more about all this....

You can still find and play the old adventure games; there even seem to be ports to the Palm. By the same token, you can still write your own versions. See Inform.