TY - JOUR A1 - Hoare, C. A. R. Tony A1 - Möller, Bernhard A1 - Struth, Georg A1 - Wehrman, Ian T1 - Concurrent Kleene Algebra T2 - Lecture Notes in Computer Science N2 - A concurrent Kleene algebra offers, next to choice and iteration, operators for sequential and concurrent composition, related by an inequational form of the exchange law. We show applicability of the algebra to a partially-ordered trace model of program execution semantics and demonstrate its usefulness by validating familiar proof rules for sequential programs (Hoare triples) and for concurrent ones (Jones's rely/guarantee calculus). This involves an algebraic notion of invariants; for these the exchange inequation strengthens to an equational distributivity law. Most of our reasoning has been checked by computer. Y1 - 2009 UR - https://opus.bibliothek.uni-augsburg.de/opus4/frontdoor/index/index/docId/68908 UR - https://nbn-resolving.org/urn:nbn:de:bvb:384-opus4-689080 SN - 9783642040801 SN - 9783642040818 SN - 0302-9743 SN - 1611-3349 VL - 5710 SP - 399 EP - 414 PB - Springer CY - Berlin ER -