Unranked Anti-Unification with Hedge and Context Variables

9 pages•Published: July 29, 2013

Abstract

In this work we study anti-unification for unranked terms and hedges, permitting context and hedge variables.
Hedges are sequences of unranked terms.
The anti-unification problem of two hedges s and q is concerned with finding their generalization, a hedge g such that both s and q are instances of g under some substitutions.
Context variables are used to abstract vertical differences in the input hedges,
and hedge variables are used to abstract horizontal differences.
A rule based system in Huet's style will be presented, which computes a set of
generalizations of input hedges and records all the differences.
The computed generalizations are least general among a certain class of generalizations.

Keyphrases: Anti-Unification with Skeletons, Generalization with Hedge and Context Variables, Least General Rigid Generalization, Parametrized Rigid Higher-Order Generalization, Unranked Higher-Order Anti-Unification

In: Konstantin Korovin and Barbara Morawska (editors). UNIF 2013. 27th International Workshop on Unification, vol 19, pages 13--21

Links:	https://easychair.org/publications/paper/Lq
	https://doi.org/10.29007/hg9q