Transformations of Conditional Rewrite Systems Revisited

We revisit known transformations of conditional rewrite systems to unconditional ones in a systematic way. We present a unified framework for describing, analyzing and classifying such transformations, discuss the major problems arising, and finally present a new transformation which has some advantages as compared to the approach of [6]. The key feature of our new approach (for left-linear confluent normal 1-CTRSs) is that it is backtracking-free due to an appropriate encoding of the conditions.

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