Minimal and complete word unification
Journal of the ACM (JACM)
The MVL theorem proving system
ACM SIGART Bulletin - Special issue on implemented knowledge representation and reasoning systems
Complexity of Makanin's algorithm
Journal of the ACM (JACM)
Makanin's Algorithm for Word Equations - Two Improvements and a Generalization
IWWERT '90 Proceedings of the First International Workshop on Word Equations and Related Topics
On the Exponent of Periodicity of Minimal Solutions of Context Equation
RTA '98 Proceedings of the 9th International Conference on Rewriting Techniques and Applications
Context Unification and Traversal Equations
RTA '01 Proceedings of the 12th International Conference on Rewriting Techniques and Applications
Currying Second-Order Unification Problems
RTA '02 Proceedings of the 13th International Conference on Rewriting Techniques and Applications
Linear Second-Order Unification
RTA '96 Proceedings of the 7th International Conference on Rewriting Techniques and Applications
Unification with Sequence Variables and Flexible Arity Symbols and Its Extension with Pattern-Terms
AISC '02/Calculemus '02 Proceedings of the Joint International Conferences on Artificial Intelligence, Automated Reasoning, and Symbolic Computation
Satisfiability of Word Equations with Constants is in PSPACE
FOCS '99 Proceedings of the 40th Annual Symposium on Foundations of Computer Science
The Mathematica Book
A uniform approach to underspecification and parallelism
ACL '98 Proceedings of the 35th Annual Meeting of the Association for Computational Linguistics and Eighth Conference of the European Chapter of the Association for Computational Linguistics
Program transformation by templates based on term rewriting
PPDP '05 Proceedings of the 7th ACM SIGPLAN international conference on Principles and practice of declarative programming
Solving equations with sequence variables and sequence functions
Journal of Symbolic Computation
Sequence unification through currying
RTA'07 Proceedings of the 18th international conference on Term rewriting and applications
Sequence disunification and its application in collaborative schema construction
WISE'07 Proceedings of the 2007 international conference on Web information systems engineering
Matching with regular constraints
LPAR'05 Proceedings of the 12th international conference on Logic for Programming, Artificial Intelligence, and Reasoning
VeriFLog: a constraint logic programming approach to verification of website content
APWeb'06 Proceedings of the 2006 international conference on Advanced Web and Network Technologies, and Applications
Well-nested context unification
CADE' 20 Proceedings of the 20th international conference on Automated Deduction
Describing lambda terms in context unification
LACL'05 Proceedings of the 5th international conference on Logical Aspects of Computational Linguistics
Anti-unification for Unranked Terms and Hedges
Journal of Automated Reasoning
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Both Sequence and Context Unification generalize the same problem: Word Unification. Besides that, Sequence Unification solves equations between unranked terms involving sequence variables, and seems to be appealing for information extraction in XML documents, program transformation, knowledge representation, and rule-based programming. It is decidable. Context Unification deals with the same problem for ranked terms involving context variables, and has applications in computational linguistics and program transformation. Its decidability is a long-standing open question. In this work we study a relation between these two problems. We introduce a variant (restriction) of Context Unification, called Left-Hole Context Unification (LHCU), to which Sequence Unification is P-reduced: We define a partial currying procedure to translate Sequence Unification problems into Left-Hole Context Unification problems, and prove the soundness of the translation. Furthermore, a precise characterization of the shape of the unifiers allows us to easily reduce Left-Hole Context Unification to (the decidable problem of) Word Unification with Regular Constraints, obtaining then a new decidability proof for Sequence Unification. Finally, we define an extension of Sequence Unification (ESU) and, closing the circle, prove the inter-P-reducibility of LHCU and ESU.