Also known as Kleene closure, Kleene operator, zero or more, Kleene star operator, 0 or more
unary operation on sets of strings, used in regular expressions for "zero or more repetitions"
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In formal language theory, the Kleene star (or Kleene operator or Kleene closure) refers to two related unary operations, that can be applied either to an alphabet of symbols or to a formal language, a set of strings (finite sequences of symbols).
The Kleene star operator on an alphabet V generates the set V* of all finite-length strings over V, that is, finite sequences whose elements belong to V; in mathematics, it is more commonly known as the free monoid construction. The Kleene star operator on a language L generates another language L*, the set of all strings that can be obtained as a concatenation of zero or more members of L. In both cases, repetitions are allowed.
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Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).