This Festschrift volume contains 28 refereed papers including personal memories, essays, and regular research papers by close collaborators and friends of José Meseguer to honor him on the occasion of his 65th birthday. These papers were presented at a symposium at the University of Illinois at Urbana-Champaign on September 23-25, 2015. The symposium also featured invited talks by Claude and Hélène Kirchner and by Patrick Lincoln. The foreword of this volume adds a brief overview of some of José's many scientific achievements followed by a bibliography of papers written by José.

This permits dealing with operational and denotational issues within the same model theory and logic. A programming language called Maude whose modules are rewriting logic theories is defined and given denotational and operational semantics. Maude provides a simple unification of concurrent programming with functional and object-oriented programming and supports high level declarative programming of concurrent systems.

Equational logic appears as a special refinement of the general framework; this supports a natural unification of the functional and concurrent programming paradigms with a purely declarative style. Throughout the paper, the concurrent nature of term rewriting is emphasized; the role of rewriting as a unified model of concurrency is also discussed.

A sublanguage called Simple Maude that can be implemented with reasonable efficiency on a wide variety of parallel architectures is described in the context of the wide-spectrum nature of Maude, and the way in which conventional code and heterogeneous systems can be integrated as 'black boxes' in a concurrent environment is explained. The use of rewriting logic for specification and programming of concurrent systems is illustrated with examples, and its generality as a concurrency model is discussed."

This book constitutes revised selected papers from the 12th International Workshop on Rewriting Logic and Its Applications, WRLA 2018, held in Thessaloniki, Greece, in June 2018. The 12 full papers presented in this volume were carefully reviewed and selected from 21 submissions. They deal with rewriting, a natural model of computation and an expressive semantic framework for concurrency, parallelism, communication, and interaction, and its applications.

This book is for researchers in computer science, mathematical logic, and philosophical logic. It shows the state of the art in current investigations of process calculi with mainly two major paradigms at work: linear logic and modal logic. The combination of approaches and pointers for further integration also suggests a grander vision for the field.

Maude is a language and system based on rewriting logic. In this comprehensive account, you’ll discover how Maude and its formal tool environment can be used in three mutually reinforcing ways: as a declarative programming language, as an executable formal specification language, and as a formal verification system. Examples used throughout the book illustrate key concepts, features, and the many practical uses of Maude.