Regular Expressions and Transducers Over Alphabet-Invariant and User-Defined Labels

• Type: Article in International Scientific Journal
• Date: 2020

Authors

Konstantinidis, S (Author) Other; Nelma Moreira (Author) FCUP; Rogério Reis (Author) FCUP; Young, J (Author) Other

Journal

Title: International Journal of Foundations of Computer Science

Vol. 31

Pages: 983-1019

ISSN: 0129-0541

Publisher: World Scientific

Indexing

ISI Web of Knowledge - 3 Citations

Scopus - 3 Citations

Other information

Authenticus ID: P-00Q-YGE

DOI: 10.1142/s0129054120420010

Abstract (EN): We are interested in regular expressions and transducers that represent word relations in an alphabet-invariant way - for example, the set of all word pairs u,v where v is a prefix of u independently of what the alphabet is. Current software systems of formal language objects do not have a mechanism to define such objects. We define transducers in which transition labels involve what we call set specifications, some of which are alphabet invariant. In fact, we give a more broad definition of automata-type objects, called labelled graphs, where each transition label can be any string, as long as that string represents a subset of a certain monoid. Then, the behavior of the labelled graph is a subset of that monoid. We do the same for regular expressions. We obtain extensions of a few classic algorithmic constructions on ordinary regular expressions and transducers at the broad level of labelled graphs and in such a way that the computational efficiency of the extended constructions is not sacrificed. For transducers with set specs we obtain further algorithms that can be applied to questions about independent regular languages as well as a decision question about synchronous transducers.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 37