Rational Term Rewriting
نویسندگان
چکیده
Rational terms (possibly innnite terms with nitely many subterms) can be represented in a nite way via-terms, that is, terms over a signature extended with self-instantiation operators. For example, f ! = f(f(f(: : :))) can be represented as x:f(x) (or also as x:f(f(x)), f(x:f(x)),. . .). Now, if we reduce a-term t to s via a rewriting rule using standard notions of the theory of Term Rewriting Systems, how are the rational terms corresponding to t and to s related? We answer to this question in a satisfactory way, resorting to the definition of innnite parallel rewriting proposed in 7]. We also provide a simple, algebraic description of-term rewriting through a variation of Meseguer's Rewriting Logic formalism.
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