version 1 . 0 , compiled 2010 - 06 - 18 23 : 23 Magically Constraining the Inverse Method with 1 : Dynamic Polarity Assignment

Abstract

Given a logic program that is terminating and mode-correct in an 6: idealised Prolog interpreter (i.e., in a top-down logic programming engine), a 7: bottom-up logic programming engine can be used to compute exactly the same 8: set of answers as the top-down engine for a given mode-correct query by rewrit9: ing the program and the query using the Magic Sets Transformation (MST). In 10: previous work, we have shown that focusing can logically characterise the stan11: dard notion of bottom-up logic programming if atomic formulas are statically 12: given a certain polarity assignment. In an analogous manner, dynamically assign13: ing polarities can characterise the effect of MST without needing to transform 14: the program or the query. This gives us a new proof of the completeness of MST 15: in purely logical terms, by using the general completeness theorem for focusing. 16: As the dynamic assignment is done in a general logic, the essence of MST can 17: potentially be generalised to larger fragments of logic. 18:

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Cite this paper

@inproceedings{Chaudhuri2010version1, title={version 1 . 0 , compiled 2010 - 06 - 18 23 : 23 Magically Constraining the Inverse Method with 1 : Dynamic Polarity Assignment}, author={Kaustuv Chaudhuri}, year={2010} }