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From: thom@ecrc.de (Thom Fruehwirth)
Subject: Re: infinite nesting -- decidable ???
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Date: Mon, 7 Nov 1994 09:29:30 GMT
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Xref: glinda.oz.cs.cmu.edu comp.lang.prolog:11585 comp.theory:11066

If the program observes certain syntactic restrictions -
e.g. as in your example monadic and each goal in the body 
contains at most one variable -
then it is decidable, for more details see:

T.~{Fr\"{u}hwirth}, E.~Shapiro, M.~Vardi, and E.~Yardeni.
Logic Programs as Types for Logic Programs,
6th Annual IEEE Symposium on Logic in Computer Science (LICS), (G. Kahn, ed.),
Amsterdam, July 1991.

thom

