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$Stalag99{"URL"}="http://stalag99.keenspace.com";

Says strredwolf:

$d and $q.

OK, that just makes no sense at all. A state variable has to record state. The only thing $q is used for is to match the subtitution on the right side of the s{}{} with the pattern on the left. It's just a table lookup. In fact, an earlier version of the program omitted $q and just had:

  redo if s/`I($z)/$1/;
  redo if s/``K($z)($z)/$1/;
  redo if s/```S($z)($z)($z)/``$1$3`$2$3/;
  ...
[download]

I think the program probably would work fine with that change, although it would be less interesting. (It would sometimes go into an infinite loop for most interesting values of $_.)

As for $d, it's only used internal to the regex itself, so it's obviously impossible that it could be a state variable.

The loop, of course, is conditional on $N.

Of course, but $N never takes on any value except 0 or 1. State machines are normally understood to have more than two states.

If what you're saying is that this is a state machine because it uses variables, then Oracle 8 is also a mere state machine.

I'm thinking of state machine in terms of FidoNet's documents there. But as I said before, it has some Virtual Machine into it. Oh where's my previous obfusc...

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$Stalag99{"URL"}="http://stalag99.keenspace.com";