Kleene star

(text)

(Or "Kleene closure", named after Stephen Kleene) The postfix "*" operator used in regular expressions, Extended Backus-Naur Form, and similar formalisms to specify a match for zero or more occurrences of the preceding expression. For example, the regular expression "be*t" would match the string "bt", "bet", "beet", "beeeeet", and so on.

This article is provided by FOLDOC - Free Online Dictionary of Computing (foldoc.org)

Mentioned in

References in periodicals archive

In addition, all the usual finite-state closure operations are supported: union, concatenation, Kleene star, and intersection.

There are really only three things that an FSA can do: concatenation (put two symbol sequences in sequence), union (choose between two different symbol sequences), or Kleene star (repeat some symbol sequence).

This is not a regular expression, since superscripts go beyond concatenation, union, and Kleene star. Such a language cannot be described with an FSA.

The finite-state playground

Axioms (1)-(11) say that the structure is an idempotent semiring under +, [center dot], 0, and 1, and the remaining axioms (12)-(17) say essentially that * behaves like the Kleene star operator of formal language theory or the reflexive transitive closure operator of relational algebra.

Kleene algebra with tests

Other topics discussed include tropical analysis of plurisubharmonic singularities, Kleene stars and cyclic projectors in the geometry of Max cones, a tropical version of the Schauder fixed point theorem, and minimum representing measures in idempotent analysis.

Tropical and idempotent mathematics; proceedings

All content on this website, including dictionary, thesaurus, literature, geography, and other reference data is for informational purposes only. This information should not be considered complete, up to date, and is not intended to be used in place of a visit, consultation, or advice of a legal, medical, or any other professional.