Modularity of Termination of TRS under Fair Strategies
نویسندگان
چکیده
We define a new notion of fairness for term rewriting system (TRS). We prove the modularity of termination of TRS under such fair strategies, that is, two TRS terminate under fair strategies if and only if their disjoint union terminates under fair strategies. In order to do so, we demonstrate that termination under fair strategies of a TRS is equivalent to the TRS being weakly terminating and globally finite. We then use modularity of weakly terminating and globally finite TRS to obtain our modularity result. We also introduce a notion of probabilistic fairness and show that termination of a TRS under a “reasonable randomized fair strategy” is equivalent to termination of the same TRS under fair strategies. The randomized version of all our results follows straightforwardly.
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