[Jscheme-user] Fwd: Mutant Marsupials

[Ken A. <kan...@bb...>]

We did something like this for a demo in the 80's once.  But, luckily we turned something less lethal like a jeep into something else, like a submarine and had to add behavior, rather than subtract it.

What the programmers should have done was make a superclass, though that doesn't seem quite right.  Maybe some kind of behavioral architecture, like subsumption that would say something like "when under attack, flee to safety and if you can return fire".

k 

>To: Ken Anderson <kan...@bb...>
>From: Geoffrey Knauth <ge...@kn...>
>Subject: Fwd: Mutant Marsupials
>Date: Fri, 9 Jul 2004 12:32:06 -0400
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>The perils of object-oriented code reuse.  --Geoff
>
>Forwarded message (from xBBN list):
>
>[ gra...@at... ]
>
>I saw this on a web site and thought, SIMNET!!
>
> Mutant Marsupials Take Up Arms Against Australian Air Force
>
>The reuse of some object-oriented code has caused tactical headaches for Australia's armed forces. As virtual reality simulators assume larger roles in helicopter combat training , programmers have gone to great lengths to increase the realism of the their scenarios, including detailed landscapes and -- in the case of the Northern Territory's Operation Phoenix -- herds of kangaroos (since groups of disturbed animals might well give away a helicopters position).
>
>The head of the Defense Science and Technology Organization's Land Operations/Simulations division reportedly instructed developers to model the local marsupials' movements and reaction to helicopters.
>
>Being efficient programmers, they just re-appropriated some code originally used to model infantry detachments reactions under the same stimuli, changed the mapped icon from a soldier to a kangaroo, and increased the figures' speed of movement.
>
>Eager to demonstrate their flying skills for some visiting American pilots, the hotshot Aussies "buzzed" the virtual kangaroos in low flight during a simulation. The kangaroos scattered, as predicted, and the Americans nodded appreciatively . . . and then did a double-take as the kangaroos reappeared from behind a hill and launched a barrage of stinger missiles at the hapless helicopter. (Apparently the programmers had forgotten the remove "that" part of the infantry coding).
>
>The lesson? Objects are defined with certain attributes, and any new object defined in terms of the old one inherits all the attributes. The embarrassed programmers had learned to be careful when reusing object-oriented code, and the Yanks left with the utmost respect for the Australian wildlife.
>
>Simulator supervisors report that pilots from that point onwards have strictly avoided kangaroos, just as they were meant to.
>
>...okay, so in essence it's true snopes.com puts in the real context...
>
>Graeme