J. Meseguer. A logical theory of concurrent objects and its realization in the MAUDE language. In G. Agha, A. Yonezawa, and P. Wegner, editors, Research Directions in Concurrent Object Oriented Programming. MIT Press, Cambridge, Ma, U.S.A., 1992.  Home/Search   Document Not in Database   Summary   Related Articles   Check

....of the language CafeOBJ [23] In this language states and transitions are modeled, respectively, as objects and arrows belonging to the same rewrite model which is a categorical extension of the algebraic structure. Meseguer s rewriting logic is also the basis of the speci cation language Maude [24]. The speci cation language Troll [25] should be mentioned as one of the main 18 practical achievements in the eld. Troll is oriented to the speci cation of objects where a method (event) is speci ed by means of evaluation rules similar to equations on attributes. Although the semantics of ....

J. Meseguer. A logical theory of concurrent objects and its realization in the Mode language. In: Research Directions in Concurrent Object-Oriented Programming. The MIT Press, Cambridge, Mass., 1993, pp. 314-390.

....references) for interpreting programs according to their speci ed semantics. Perhaps also Maude s object oriented modules could be exploited to express the intended operational semantics more concisely, following the speci cation style for concurrent object oriented systems illustrated in [6, 9, 10]. But an SOS description of a practical programming language is likely to be rather large regardless of its degree of modularity and this might provoke problems with the eciency of the interpretation. An alternative approach would be to exploit action semantics as an intermediate step. The ....

J. Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In G. Agha, P. Wegner, and A. Yonezawa, editors, Research Directions in Object-Based Concurrency, pages 314-390. The MIT Press, 1993.

....is an integrated software development environment for specifying and animating Troll and omTroll specifications. There are other approaches to developing object specification languages with a sound theoretical basis. The ones most closely related to ours are Foops [GM87, RS92, GS95] and Maude [Mes93] Foops is based on Obj3 [GW88] which is in turn based on equational logic. Maude is based on rewriting logic that is a uniform model of concurrency [Mes92] Many other language projects work on related ideas, e.g. Ooze [AG91] Albert [DDPW94] Lcm [FW93] and Etoile [AB95] The languages and ....

J. Meseguer. A Logical Theory of Concurrent Objects and Its Realization in the Maude Language. In G. Agha, P. Wegener und A. Yonezawa, Hrsg., Research Directions in Object-Oriented Programming, pages 314--390. MIT Press, 1993

....logic suffices. We believe such a system to be more accessible than type theory, as knowledge of first order logic is required in most undergraduate programs in computer science or engineering. Moreover, this logic has very fast 12 automatic theorem provers available at present, such as Maude, [17, 6]. Rewriting systems usually work by following a proof template given by the user, and then automatically filling in the details using the rewriting rules. This would enable the producer to send only a proof score rather than a full proof. Because the sizes of the proofs in the ELF in ....

Jos'e Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In Gul Agha, Peter Wegner, and Aki Yonezawa, editors, Research Directions in Object-Based Concurrency. MIT, 1993.

....of thesystem andoftheinvariants. From themultitudeofformalisms addressing concurrentsystems, our focus is on onedue toMeseguer called rewriting logic [Mes92, Mes96] There exist languages that are especially tailored for specifications in rewriting logic, and the most importantofthese is Maude[Mes93] However, atthetimethework reported here was initiated no implementation of Maudewas available. Our choice therefore fell upon OBJ3 [GWM 96] mainly because it offers the possibilityof order sorted specifications, a feature weshall makeintensive use of, andsecond because methods ....

J. Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In Gul Agha, Peter Wegner, and Akinori Yonezawa, editors, Research Directions in Concurrent Object-OrientedProgramming, pages 314--390. MIT Press, 1993.

....is seldom (if ever) the case that parallel or distributed imple 5 The program formulae are represented by (p Omega r) and (q Omega s) in the Proof Net. 6 As a matter of fact, a broadcast mechanism has been recently implemented on top of the rewriting logic programming language MAUDE [16]. 11 mentation platforms provide broadcast communication as a primitive. Instead one to one asynchronous message passing seems to be predominant, and we have therefore focused on how to implement (in an abstract sense) broadcast communication when one to one asynchronous message passing is ....

J. Meseguer. A logical theory of concurrent objects and its realization in the MAUDE language. In G. Agha, A. Yonezawa, and P. Wegner, editors, Research Directions in Concurrent Object Oriented Programming. MIT Press, Cambridge, Ma, U.S.A., 1992.

....Research on reflective object oriented systems has shown many practical advantages (see [5] for some recent papers) However, reflective object systems lack at present a rigorous semantics. Since rewriting logic has already been shown to be a good semantic framework for object oriented systems [11], we conjecture that it will prove very useful as a semantic framework for object oriented reflection [16] ffl Semantics of distributed and mobile reflective systems. Reflective object systems have a natural extension to distributed and mobile systems. In particular, mobility, because of its ....

J. Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In G. Agha, P. Wegner, and A. Yonezawa, editors, Research Directions in Concurrent Object-Oriented Programming, pages 314--390. MIT Press, 1993.

.... gas to each network entity, and time passes when each entity has used up its gas or has no transitions. 2 Concurrent Objects in Rewriting Logic We brie y introduce the rewriting logic model for concurrent object systems that we use for our network model. Following the approach of Meseguer [15], the concurrent state of an object system, called a con guration, has the struc2 Mason Talcott ture of a multiset made up of objects and messages. The associativity and commutativity of a con guration s multiset structure makes it very uid. We can think of it as a soup in which objects and ....

J. Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In G. Agha, P. Wegner, and A. Yonezawa, editors, Research Directions in Object-Based Concurrency. The MIT Press, 1993.

....and a set E of equations that are Church Rosser and terminating modulo A; that is, the equational part must be equivalent to a functional module. For some axioms A, this can be checked using a Church Rosser checker as the one presented in [12, 9, 6] The rules R in the module are coherent [15, 16] with the equations E modulo A. This means that appropriate critical pairs exist between rules and equations, allowing us to intermix rewriting with rules and rewriting with equations without losing rewrite computations by failing to perform a rewrite that would have been possible before an ....

.... in which we have a set of equations executed by rewriting, which can also be seen as a set of rules interpreted equationally, and a set of rewrite rules without an equational interpretation, the property of coherence ensures a correspondence between operational behavior and intended semantics [15, 16]. Given a set of rules R = fl i r i g, the rewrite relation R is the smallest relation stable by context and instantiation containing l i R r i for each l i r i 2 R. For any relations R and S , we de ne R=S = S R S . In particular, when S is the replacement relation S ....

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Jose Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In Gul Agha, Peter Wegner, and Akinori Yonezawa, editors, Research Directions in Object-Based Concurrency, pages 314-390. The MIT Press, 1993.

.... as [35, 41, 45] There are also a number of languages which, while developed independently from Linear Logic, could be reconstructed in terms of the fragment of simple LinLog where the connective never occurs in goals: in general, all shared data space languages can be reconstructed in this way [26, 9, 14, 40, 13], with their computations corresponding to proof search along a single branch. For these languages, the could be used to reconstruct externally the behavior of programs with respect to different possible initial states (which would be conjoined together in the root sequent of a proof 4 ) ....

J. Meseguer. A logical theory of concurrent objects and its realization in the MAUDE language. In G. Agha, A. Yonezawa, and P. Wegner, editors, Research Directions in Concurrent Object Oriented Programming. MIT Press, Cambridge, Ma, U.S.A., 1992.

.... of connecting the worlds of a formal specification language such as Maude [1] and of a model for open distributed systems such as CORBA [5] Maude is an executable rewriting logic [3] language particularly well suited for the specification of object oriented open and distributed systems [4]. CORBA is one of the leading object and component platforms in the market, specially well suited for the implementation of distributed applications in open systems. By allowing objects of both worlds to seamlessly interoperate, we can obtain several interesting results. In the first place, ....

....of systems. Thus, Maude integrates an equational style of functional programming with rewriting logic computation. This logic can naturally deal with state and with highly nondeterministic concurrent computations; in particular, it supports very well concurrent object oriented computation [4]. Such a logic allows us to specify functional as well as non functional properties. In Maude, object oriented systems are specified by object oriented modules in which classes and subclasses are declared. Each class is declared using the syntax class C a 1 : S 1 , a n : S n , where C ....

Jose Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In Gul Agha, Peter Wegner, and Akinori Yonezawa, editors, Research Directions in Object-Based Concurrency, pages 314--390. The MIT Press, 1993.

....are accepted or refused by objects, the sequences of messages an object accepts, or whether deadlock is possible. The verification of both sequential and concurrent programs quickly becomes so complex that there is a strong need for abstraction. The first level of abstraction is provided by Maude [4], an object oriented specification language for concurrent systems. Particular to Maude is a very abstract way of specifying the synchronization and communication between objects. Moreover, Maude s unconventional object model enables the harmonic integration of the two concepts of concurrency and ....

....We verify a mutual exclusion property of a specification in Maude, and we identify a class of properties that is inheritable by Maude s inheritance relation. 1 [2] is a longer version of this paper. 1 2 Maude This section briefly introduces Maude. For a more detailed overview see [4]. Maude has two parts: one which is functional (the specification language OBJ3) and another which specifies states (so called configurations) and state changes. The state modeling part is specified by an operational (state transition) semantics given by transition rules. The state of a Maude ....

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J. Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In G. Agha, P. Wegner, and A. Yonezawa, editors, Research Directions in Concurrent Object-Oriented Programming, pages 314--390. MIT Press, 1993. 8

....behavior locally to processes, but the programming paradigm of CTR differs from the one that is induced by using distributed temporal logics as the basis for object oriented languages. Among other approaches to developing object specification languages with a sound theoretical basis, MAUDE (Meseguer 1993, Clavel et al. 1996) also deals with concurrency. It is based on rewriting logic (Meseguer 1992) that is a uniform model of concurrency. Gnome (Sernadas et al. 1994) is based on temporal logic, it is most closely related to Troll although the semantics is not capable of expressing noninterleaving ....

Meseguer, J. (1993) A Logical Theory of Concurrent Objects and its Realization in the Maude Language, in Research Directions in Concurrent Object-Oriented Programming (eds. Agha, G. and Wegner, P. and Yonezawa, A.), pages 314-- 390. The MIT Press.

....variety of different modal or temporal logics can be chosen. We consider Distributed Temporal Logic (Dtl) ECSD98] a logic which is especially suited for capturing the nature of distributed systems. We intend to use temporal logic to express the dynamics of object oriented specifications in Maude [Mes93] which is based on rewriting logic. We generalize Dtl to Dtl since Dtl assumes synchronous communication. In Maude systems, object communication may be synchronous, asynchronous, or a combination of both. The main emphasis of Dtl is to directly reflect the concurrent nature of a distributed ....

.... extended Maude specification can be translated into a rewrite theory R = Sigma; E; L; R) where Sigma = S; Omega Gamma is a signature with sorts S and operation symbols Omega Gamma The desugaring process of transforming object oriented modules to system modules was originally described in [Mes93]. The currently implemented version of flattening objectoriented modules to system modules is presented in [CDELM98,DM98] For our purposes it is sufficient to point out which sorts and operations we assume to be at least in Sigma. Thus, we will not go into the details of transforming ....

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J. Meseguer. A Logical Theory of Concurrent Objects and Its Realization in the Maude Language. In G. Agha, P. Wegner, and A. Yonezawa, editors, Research Directions in Concurrent Object-Oriented Programming, pages 314--390. The MIT Press, 1993.

....SSG 91] and TROLL [JSHS96] have been developed for supporting the specification of objects and their dynamic behaviour based on temporal or dynamic logics. Of course there are other formal approaches to specifying dynamic behaviour of objects. For instance, conditional term rewriting [Mes93] is another way of describing object behaviour. The specification language Maude [Mes92, MQ93] is based on a conditional term rewriting semantics. However, all these approaches to specifying information systems assume that the dynamic behaviour of the system and its parts is totally known at ....

J. Meseguer. A Logical Theory of Concurrent Objects and Its Realization in the Maude Language. In G. Agha, P. Wegener, and A. Yonezawa, editors, Research Directions in Object-Oriented Programming, pages 314--390. MIT Press, 1993.

.... generalizes our proposals in [3, 2] where the declarative speci cation of concurrent objects was addressed in the context of a concrete operational model (the Lpi language) In this aspect, this work is related to approaches where an underlying process calculus is taken as the speci cation target [11, 12], although we do not depart from any operational model. Some adaptations of Hennessy Milner logics and calculi to mobile process calculi have been proposed, for instance [15, 6] However, such formalizations have been proposed for speci c operational models, and aimed at obtaining logical ....

J. Meseguer. A Logical Theory of Concurrent Objects and Its Realization in the Maude Language. In G. Agha, P. Wegner, and A. Yonezawa, editors, Trends in Object-Based Concurrent Computing, pages 314-390. MIT Press, Cambridge, MA, 1993.

....[DDP93] Oblog [SSE87; SSG 91] Gnome [SR94] and Troll [JSHS96] have been developed for supporting the specification of objects and their dynamic behaviour. Of course there are other formal approaches to specifying dynamic behaviour of objects. For instance, conditional term rewriting [Mes93] is another way of describing object behaviour and is the formal foundation behind the specification language Maude [Mes92; MQ93] In the database area a lot of interesting work concerning the description of database dynamics (e.g. in [LT93; BK98] can be found. In contrast to other approaches ....

J. Meseguer. A Logical Theory of Concurrent Objects and Its Realization in the Maude Language. In G. Agha, P. Wegener, and A. Yonezawa, editors, Research Directions in Object-Oriented Programming, pp. 314--390. MIT Press, 1993.

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J. Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In G. Agha, P. Wegner, and A. Yonezawa, editors, Research Directions in Concurrent Object-Oriented Programming, pages 314--390. MIT Press, 1993.

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J. Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In Research Directions in Concurrent Object-Oriented Programming, pages 314--390. The MIT Press, 1993.

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J. Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In G. Agha, P. Wegner, and A. Yonezawa, editors, Research Directions in Concurrent Object-Oriented Programming, pages 314--390. MIT Press, 1993.

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Jose Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In Gul Agha, Peter Wegner, and Akinori Yonezawa, editors, Research Directions in Concurrent Object-Oriented Programming, pages 314{ 390. MIT Press, 1993.

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J. Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In G. Agha, P. Wegner, and A. Yonezawa, editors, Research Directions in Object-Based Concurrency, pages 314--390. The MIT Press, 1993.

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Jos'e Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In Gul Agha, Peter Wegner, and Akinori Yonezawa, editors, Research Directions in Concurrent Object-Oriented Programming, pages 314-- 390. MIT Press, 1993.

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J. Meseguer, A logical theory of concurrent objects and its realization in the Maude language, in: G. Agha, P. Wegner, and A. Yonezawa, eds., Research Directions in Object-Based Concurrency (The MIT Press, 1993) 314--390.

....engine is designed with the explicit goal of being highly extensible and of supporting rapid prototyping and formal methods applications, but its semi compilation techniques allow it to meet those goals with good performance. 1 Introduction Maude is a logical language based on rewriting logic [17,24,20]. It is therefore related to other rewriting logic languages such as Cafe [10] ELAN [12] and DLO [6] The equational language OBJ [11] can be regarded as a functional sublanguage of Maude. This paper gives an introduction to the language and its interpreter implementation. Particular emphasis ....

....for class inheritance. However, object oriented modules can be systematically translated into ordinary rewrite theories by making explicit all these assumptions. They can therefore be understood as a special case of system modules. A detailed account of this translation process can be found in [20]. omod PROTOCOL[ELT : TRIV] is protecting QUEUE[ELT] 6 Clavel et al. sort Contents Count . subsort Elt Contents . op z : Count . op s : Count Count . op empty : Contents . msg to: OId Elt Count Msg . data to receiver msg to:ack : OId Count Msg . ....

[Article contains additional citation context not shown here]

Jos'e Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In Gul Agha, Peter Wegner, and Akinori Yonezawa, editors, Research Directions in Concurrent Object-Oriented Programming, pages 314-- 390. MIT Press, 1993.

....interaction, and asynchronous communication by message passing. It is of course possible to represent a concurrent object system as a rewrite theory with di erent modeling styles and adopting di erent notational conventions. What follows is based on a particular style of representation [34] that has proved useful and expressive in practice, and that is supported by Full Maude s object oriented modules [9, 6] To model a concurrent object system as a rewrite theory, we have to explain two things: 1. how the distributed states of such a system are equationally axiomatized and ....

J. Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In G. Agha, P. Wegner, and A. Yonezawa, editors, Research Directions in Concurrent Object-Oriented Programming, pages 314-390. MIT Press, 1993.

....only an optional part of the righthand side, i.e. that it can be omitted in some rules so that the object is then deleted. In addition, p new objects may be created, and q new messages may be generated for p; q 0. The above representation of objects is the one adopted in the Maude language [112, 127, 116] and implicitly assumes globally unique names. Other representations are of course possible. For example, in her theory of actors and actor components, Carolyn Talcott adopts instead a more abstract representation of objects as abstract actors [153] where objects can be renamed by a form of ....

....different forms of verification. Furthermore, a compiler has been developed in addition to the Cafe interpreter implementation [136, 71] In our group at SRI, Manuel Clavel, Francisco Dur an, Steven Eker, Patrick Lincoln and I have been working on the implementation of an interpreter for Maude [127, 116, 32, 31]. After several experimental versions, a beta release has been finished in March 1998 [31] and a full distribution is planned for the Fall of 1998. The equational logic underlying Maude s rewriting logic is membership equational logic [120, 21] Maude s functional modules are Church Rosser and ....

J. Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In G. Agha, P. Wegner, and A. Yonezawa, editors, Research Di- rections in Concurrent Object-Oriented Programming, pages 314--390. MIT Press, 1993.

No context found.

J. Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In G. Agha, P. Wegner, and A. Yonezawa, eds., Research Directions in Concurrent Object-Oriented Programming, pp. 314-390. MIT Press, 1993.

....interaction (which corresponds to synchronous communication) and asynchronous communication we have to add rewrite rules that operate on a group of tokens. One possible realization is to view tokens as objects in the sense of the rewriting logic approach to concurrent object oriented programming [49], where rewrite rules operate on a multiset of objects that are interrelated by object references. As we have already pointed out, recent work on partial order semantics for object oriented systems speci ed in rewriting logic in this manner [58] is in fact very close to the safe process semantics ....

J. Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In G. Agha, P. Wegner, and A. Yonezawa, editors, Research Directions in Concurrent Object-Oriented Programming. MIT Press, 1993.

....with theories structured in some way and result in an unstructured, or less structured, speci cation. That is, structured theories are often attened when being composed. There are 2 Object oriented modules are used to specify object oriented systems but can be desugared into system modules [38,22,18]. 3 however good reasons for preserving their structure. Besides the obvious understandability and design documentation reasons, it is often very useful to consider theory building operations whose results are structured theories. For example, re ning a software design can be best understood as ....

....a speci cation language. With this speci cation we have endowed Full Maude with a module algebra in the Clear OBJ tradition, including module hierarchies, parameterized modules, views, and module expressions. In addition, Full Maude also allows the use of modules with object oriented notation [38,22,18]. The module algebra thus obtained is easily extensible: A user may easily de ne new module transformations and module operations; that is, the user can not only do metaprogramming by using the module operations provided in the module algebra of the language, but can also do meta metaprogramming ....

J. Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In G. Agha, P. Wegner, and A. Yonezawa, editors, Research Directions in Object-Based Concurrency, pages 314-390. The MIT Press, 1993.

....level without any need for using rewriting logic metalevel features. 2 Denker, Meseguer Talcott concept of composable service in a distributed object oriented system. Our approach is based on the executable formal semantics for distributed objectoriented systems provided by rewriting logic [19] and explicitly addresses the re ective distributed object oriented properties that are essential for having a truly modular notion of service. The formal model that we present seems promising not only for formal analysis and symbolic simulation, but also as a semantic foundation on top of which ....

....[16,18,20] to the case of asynchronous message passing. We then introduce meta objects, which can be layered to form towers that appear to their environment just like concurrent objects. 2. 1 Concurrent Objects in Rewriting Logic We adopt the treatment of concurrent objects by rewrite theories in [19]. We call such theories concurrent object theories. The concurrent state of an object oriented system, often called a con guration, has typically the structure of a multiset made up of objects and messages. Therefore, we can view con gurations as built up by a binary multiset union operator, which ....

J. Meseguer. A Logical Theory of Concurrent Objects and Its Realization in the Maude Language. In G. Agha, P. Wegner, and A. Yonezawa, editors, Research Directions in Concurrent Object-Oriented Programming, pages 314-390. The MIT Press, 1993.

....the e ect of time advance on a con guration of objects and messages, and the maximum time elapse of a con guration, and to let these functions distribute over the elements in a con guration. However, we showed in [17] that the introduction of a function can easily lead to lack of coherence [7,19,12] in the rewrite theory, which intuitively corresponds to the possibility of having ill timed rewrites where the con guration being rewritten is (a subterm of) an argument of , and therefore is an aged state. Furthermore, rewrites of terms of sort Configuration together with a function mte : ....

J. Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In G. Agha et al., editors, Research Directions in Concurrent Object-Oriented Programming, pages 314-390. MIT Press, 1993.

....QI not in database) fi if not unitInDatabase(QI, DB) ceq evalModExp(ME, PL, DB) DB if unitInDatabase(ME, DB) endfm 7. 6 The Transformation of Object Oriented Modules to System Modules A discussion on the transformation of object oriented modules into system modules can be found in [44, 27, 14, 26]. We focus here on the part of the process accomplished by each of the main functions involved in the transformation. The transformation discussed in [27] assumed that object oriented modules were attened before being transformed into system modules. However, doing it in this way, the ....

....class and of their subclasses. The set of attributes of the objects appearing in the membership axioms, equations, and rewriting rules are completed, so that the default convention of not having to exhaustively mention the set of attributes of a class is supported. Note that in Meseguer s paper [44] a parallel hierarchy of sorts was de ned to deal with objects in di erent classes, and membership axioms constraining the objects to their corresponding sorts were added. The transformation could be easily completed with sorts, subsort relations, and membership constraints as indicated there. In ....

Jose Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In Gul Agha, Peter Wegner, and Akinori Yonezawa, editors, Research Directions in Object-Based Concurrency, pages 314-390. The MIT Press, 1993.

....to equational theorem proving in OBJ proposed by Joseph Goguen [13, 14] We have benefited considerably from Joseph Goguen s advice and from the OBJ experience in the design of the inductive theorem prover. 2 A Reflective Kernel in Maude Maude is a logical language based on rewriting logic [21, 26, 22]. An introduction to Maude and its interpreter implementation can be found in [7, 5, 6] For our present 6 purposes the key point is that the Maude implementation supports an arbitrary number of levels of reflection and gives the user access to important reflective capabilities, including the ....

J. Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In G. Agha, P. Wegner, and A. Yonezawa, editors, Research Directions in Concurrent Object-Oriented Programming, pages 314--390. MIT Press, 1993.

.... nets, including place transition nets, contextual nets, algebraic nets, colored nets, and timed Petri nets [218,223,293,297,268,289] 6) Gamma and the Chemical Abstract Machine [218] 7) CCS and LOTOS [230,208,314,45,89,311,309,201] 8) the calculus [316,292] 9) concurrent objects and actors [218,220,300,302,304]; 10) the UNITY language [218] 11) concurrent graph rewriting [223] 12) dataflow [223] 13) neural networks [223] 14) real time systems, including timed automata, timed transition systems, hybrid automata, and timed Petri nets [268,262] and (15) the tile logic [146,147,135] model of ....

....and case studies, an environment, and a collection of theorem proving tools supporting different forms of verification. Furthermore, a compiler has been developed in addition to the Cafe interpreter implementation [260,165] The Maude language has been developed at SRI, in Menlo Park, California [220,80,69,74,71]. The equational logic underlying Maude s rewriting logic is membership equational logic [226,30,31] and gives rise to a sublanguage of functional modules. System modules specify general rewrite theories, and object oriented modules provide syntactic sugar for object oriented rewrite theories. ....

Jos'e Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In G. Agha, P. Wegner, and A. Yonezawa, editors, Research Directions in Concurrent Object-Oriented Programming, pages 314--390. The MIT Press, 1993.

No context found.

J. Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In G. Agha, P. Wegner, and A. Yonezawa, editors, Research Directions in Object-Based Concurrency, pages 314--390. The MIT Press, 1993.

....advantages to be gained from the correspondence between reasoning theories and rewriting logic theories. Perhaps the most obvious is the ability to use implementations of rewriting logic to prototype systems described in terms of reasoning theories. Using a reflective implementation such as Maude [17,2] the control layer of an OMRS can also be specified using a strategy language. A key objective of the OMRS effort is to provide modular descriptions of mechanized reasoning systems and to build systems out of lean, wellunderstood modules that interact in meaningful ways to provide an overall ....

Jos'e Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In Gul Agha, Peter Wegner, and Akinori Yonezawa, editors, Research Directions in Concurrent Object-Oriented Programming, pages 314-- 390. MIT Press, 1993.

.... semantics) for the instantiate function is given by the equation instantiate(M [X : T ] V ) M [V ] 4 From Object Oriented Modules to System Modules Our exposition assumes familiarity with the logical theory of concurrent objects and the syntax for object oriented modules discussed in [15]. We briefly recall the most basic ideas, and then present the syntax for the object oriented modules, its representation at the metalevel, and the translation of objectoriented modules into system modules. In a concurrent object oriented system the concurrent state, which is usually called a ....

....introduced to range over the additional attributes that may appear. That is, each object O : C : appearing in a rule, is translated into O : X : Atts where the new variable X is declared of sort C Class and the new variable Atts of sort AttributeSet. ffl As described in [15], we simplify the notation used in object oriented modules by giving the user the possibility of not mentioning in a given rule those attributes of an object that are not relevant for that rule. To explain this convention, let a : v denote the attribute value pairs a 1 : v 1 ; a n : v n , ....

[Article contains additional citation context not shown here]

Jos'e Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In G. Agha, P. Wegner, and A. Yonezawa, editors, Research Directions in Object-Based Concurrency, pages 314--390. The MIT Press, 1993.

....E 0 of equations that are Church Rosser, terminating, and sort decreasing modulo A; that is, the equational part must satisfy the same requirements as a functional module. Moreover, we require that the rules R in the module are coherent [67] or at least what might be called weakly coherent [44,68]) with the equations E 0 modulo A. This means that appropriate critical pairs between rules and equations are joinable, allowing us to intermix rewriting with rules and rewriting with equations without losing rewrite computations by failing to perform a rewrite that would have been possible ....

....I to state F corresponds directly to a sequence of computational rewrite steps applying the corresponding rewrite rules. 3. 4 Object Oriented Modules Among the many concurrent systems that we can specify as system modules in Maude, concurrent object oriented systems are an important subclass [44]. 19 In a concurrent object oriented system the concurrent state, which is usually called a configuration, has typically the structure of a multiset made up of objects and messages that evolves by concurrent rewriting modulo associativity, commutativity and identity, using rules that describe the ....

[Article contains additional citation context not shown here]

J. Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In G. Agha, P. Wegner, and A. Yonezawa, editors, Research Directions in Concurrent Object-Oriented Programming, pages 314--390. The MIT Press, 1993.

.... shown well suited for giving object oriented specifications of complex hybrid systems such as the steam boiler [38] and has also been applied to give semantics to the SDL telecommunications specification language [42] In fact, rewriting logic object oriented specifications in the Maude language [33] have a natural extension to TRL object oriented specifications in Timed Maude [24,38] The approach taken here is different. As already mentioned, we argue that real time systems can be specified in ordinary rewriting logic, and that reasoning about their behavior does not require a special ....

.... the set E of equations in a rewrite theory is divided into a set E 0 of simplifying equations and a set Ax of structural axioms, in such a way that the equations in E 0 define a Church Rosser and terminating set of equations modulo the set Ax , and such that the set of rules R is coherent [13,44,33] wrt. E 0 ] Ax . A rewrite theory is coherent if for every one step sequential rewrite t Gamma t 1 modulo the structural axioms Ax , there is also a rewrite t E 0 Gamma t 0 1 modulo Ax , for t E 0 an E 0 normal form of t modulo Ax , such that t 1 and t 0 1 are E equivalent. A ....

J. Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In G. Agha, P. Wegner, and A. Yonezawa, editors, Research Directions in Concurrent Object-Oriented Programming, pages 314--390. MIT Press, 1993.

....regard, besides reflection itself, a crucial feature of rewriting logic is its executable nature, so that rewriting logic specifications become executable prototypes of the languages, logics, and mappings between their representations in the framework. This is well supported by the Maude language [70, 15]. 2.4 Actor Models for Open Distributed Systems Actors are a natural basis for modeling open distributed systems. They provide units of encapsulation of control and state, interaction via asynchronous message passing, and dynamic architecture. Actor theories [86, 85, 60] were developed by ....

....axioms do not state directly what changes are performed on the system state but, instead, which properties these changes are required to satisfy. 2.5. 1 Rewriting Logic Specification of Object Systems Concurrent object based systems can be very naturally specified and executed in rewriting logic [70]. The case of asynchronous object systems such as actors has already been discussed in x2.4, but synchronous object systems or systems combining synchrony and asynchrony can be specified with equal ease. Class 5 inheritance has also a precise semantics in terms of the corresponding rewriting ....

[Article contains additional citation context not shown here]

Jose Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In Gul Agha, Peter Wegner, and Akinori Yonezawa, editors, Research Directions in Concurrent ObjectOriented Programming, pages 314--390. MIT Press, 1993.

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J. Meseguer. A logical theory of concurrent objects and its realization in the MAUDE language. In G. Agha, A. Yonezawa, and P. Wegner, editors, Research Directions in Concurrent Object Oriented Programming. MIT Press, Cambridge, Ma, U.S.A., 1992.

No context found.

J. Meseguer. A logical theory of concurrent objects and its realization in the MAUDE language. In G. Agha, A. Yonezawa, and P. Wegner, editors, Research Directions in Concurrent Object Oriented Programming. MIT Press, Cambridge, Ma, U.S.A., 1992.

No context found.

Meseguer, J., A logical theory of concurrent objects and its realization in the maude language, in: Object Oriented Programming, MIT Press, 1993 pp. 314-- 390.

No context found.

J. Meseguer. A Logical Theory of Concurrent Objects and its Realization in the Maude Language. In G. Agha, P. Wegner, and A. Yonezawa, editors, Object-Oriented Programming, pages 314 -- 390. MIT Press, 1993.

No context found.

Meseguer, J.: A logical theory of concurrent objects and its realization in the Maude language. In Agha, G., Wegner, P., Yonezawa, A., eds.: Object-Oriented Programming. MIT Press (1993) 314--390

No context found.

J. Meseguer. A logical theory of concurrent objects and its realization in the Maude language. Technical Report SRI-CSL-92-08, SRI International, July 1992.

No context found.

J. Meseguer, A Logical theory of Concurrent Objects and its Realization in the Maude Language, in: G. Agha, P. Wegner, A. Yonezawa, eds., Research Directions in Object-Based Concurrency, MIT Press (1993) 313-389

No context found.

J. Meseguer, A Logical theory of Concurrent Objects and its Realization in the Maude Language, in: G. Agha, P. Wegner, A. Yonezawa, eds., Research Directions in Object-Based Concurrency, MIT Press (1993) 313-389

No context found.

J. Meseguer. A logical theory of concurrent objects and its realization in the Maude language. In G. Agha, P. Wegner, and A. Yonezawa, editors, Research Directions in Concurrent Object-Oriented Programming, pages 314-390. MIT Press, 1993. 231

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