Discovering an Algorithm Actually Learning Restricted Single Occurrence Regular Expression with Interleaving

TL;DR

This paper critically analyzes the iSOIRE algorithm for learning restricted single-occurrence regular expressions with interleaving, revealing its limitations and providing corrected results that belong to a subclass of SOIREs.

Contribution

The paper identifies the inaccuracies in iSOIRE's learned expressions and offers a corrected analysis showing it learns a subclass of SOIREs, not the full class.

Findings

iSOIRE does not always learn true SOIREs

The corrected results belong to a subclass of SOIREs

The paper provides theoretical analysis of the algorithm's correctness

Abstract

A recent paper proposed an algorithm iSOIRE, which combines single-occurrence automaton (SOA) and maximum independent set (MIS) to learn a subclass single-occurrence regular expressions with interleaving (SOIREs) and claims the learnt expression is SOIRE, which has unrestricted usage for interleaving. However, in reality, the learnt expression still has many restrictions for using interleaving, even does for Kleene-star or interation, i.e, the learnt expression is not an SOIRE, we prove that by examples. In this paper, for the algorithm iSOIRE, we first give the basic notions, then provide analyses about incorrectness, finally present the correct result learnt by iSOIRE. Our theoretical analyses demonstrate that the result derived by iSOIRE belongs to a subclass of SOIREs.