Re: question: how to map traces onto integers?

      I'm looking for a technique to MAP arbitrary TRACES from any
      given set of GRAMMAR-RULES onto the set of natural numbers, or
      INTEGERS.


      I need this in order to be able to identify a complete trace
      (e.g. a pascal program or whatever) by a single natural
      number.


Well, I guess you could do it with something akin to Goedel numbering.
Your trace is just a sequence of tokens, right?


1) label each of the terminals in your grammar with a natural number, L
2) label the tokens in your trace with unique primes P, starting with 2
      and continuing upwards
3) each token in your trace contributes a factor P^L, with P given by
      the position in the trace and L given by the terminal your token is
      an instance of
4) your unique number is the product of the factors of all the tokens


Warning: these numbers become VERY LARGE VERY FAST. This technique is
probably only useful for theoretical considerations.


J
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