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From: dewar@gnat.com (Robert Dewar)
Newsgroups: comp.lang.ada
Subject: Re: Generation of permutations
Date: 7 May 2002 19:17:47 -0700
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tmoran@acm.org wrote in message news:<PsLB8.6706$cT1.98522399@newssvr21.news.prodigy.com>..

> So "recursively undecidable" is a fancy way of saying 
> it may get stuck in an infinite loop.

Nope! That's quite wrong. In fact it is quite easy to detect if you
are in an infinite loop. You use the same
technique as you use in a chess match to limit repeated
positions, you just remember all previous states, and if
a state is repeated, you know you are in a non-halting
situation.

So if this was all that halting was about, there would
not be a problem.