## Distributed Operational Semantics for the Object Paradigm (1997)

Venue: | Oxford University Computing Laboratory |

Citations: | 1 - 0 self |

### BibTeX

@INPROCEEDINGS{Malcolm97distributedoperational,

author = {Grant Malcolm and Corina Cirstea},

title = {Distributed Operational Semantics for the Object Paradigm},

booktitle = {Oxford University Computing Laboratory},

year = {1997}

}

### OpenURL

### Abstract

this paper we present an approach we call `Distributed Operational Semantics', which models systems of concurrent, interacting objects by diagrams which assign an operational semantics to each object in a system. The behaviour of the whole system is given by a limit construction. In modelling behaviour by limits we follow earlier work by Goguen on Categorical Systems Theory [4, 5, 6]. This approach pays particular attention to the hierarchical structure of systems, and provides means of constructing systems from component parts in a way that captures both complex objects and parallel composition with synchronisation [16]. The operational semantics of objects can be very general: for example, a semantics for the object-oriented specification language FOOPS has been given by modelling objects as unlabelled transition systems; this semantics is summarised in Section 4.2, and a full account is given in [2]. We shall also present examples of systems that use labelled transition systems. A useful property of the examples we present is that they can be readily translated into specifications in the logic programming language Eqlog [9], which provides both a simulator for the system and a logic for reasoning about systems. Like the sheaf semantics for concurrent objects originating with Goguen [8, 3] and further investigated in [22, 16, 2], our approach is essentially constraint based: interactions between objects constrain their possible behaviours, primarily by synchronising on shared subobjects. Constructing the behaviour of a system by taking its limit corresponds to solving those constraints. It is because of its constraint based nature that the translation into Eqlog is so natural. This paper provides a short introduction to Distributed Operational Semantics; a fuller acco...

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Citation Context ...true and SB --[AB]-? SB' == true and aps(SA') == SP' and bps(SB') == SP' . endo 4.2 Distributed Semantics for FOOPS (Only a sketch. A full account is given in [2].) The distributed semantics of FOOPS =-=[10]-=- is given by the limit of a functor from the category sketched in Figure 1 to the category of unlabelled transition systems. In this figure, ffifl fflfi ME i i i i i i) i i i i i1 j OC1;1 h TC1;1 \Del... |

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Citation Context ...e logic programming language Eqlog [9], which provides both a simulator for the system and a logic for reasoning about systems. Like the sheaf semantics for concurrent objects originating with Goguen =-=[8, 3]-=- and further investigated in [22, 16, 2], our approach is essentially constraint based: interactions between objects constrain their possible behaviours, primarily by synchronising on shared subobject... |

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Citation Context ...mantics to each object in a system. The behaviour of the whole system is given by a limit construction. In modelling behaviour by limits we follow earlier work by Goguen on Categorical Systems Theory =-=[4, 5, 6]-=-. This approach pays particular attention to the hierarchical structure of systems, and provides means of constructing systems from component parts in a way that captures both complex objects and para... |

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Citation Context ...[9], which provides both a simulator for the system and a logic for reasoning about systems. Like the sheaf semantics for concurrent objects originating with Goguen [8, 3] and further investigated in =-=[22, 16, 2]-=-, our approach is essentially constraint based: interactions between objects constrain their possible behaviours, primarily by synchronising on shared subobjects. Constructing the behaviour of a syste... |

3 | A distributed semantics for FOOPS
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Citation Context ... for the object-oriented specification language FOOPS has been given by modelling objects as unlabelled transition systems; this semantics is summarised in Section 4.2, and a full account is given in =-=[2]-=-. We shall also present examples of systems that use labelled transition systems. A useful property of the examples we present is that they can be readily translated into specifications in the logic p... |

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Systems and minimal realization
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Citation Context ...mantics to each object in a system. The behaviour of the whole system is given by a limit construction. In modelling behaviour by limits we follow earlier work by Goguen on Categorical Systems Theory =-=[4, 5, 6]-=-. This approach pays particular attention to the hierarchical structure of systems, and provides means of constructing systems from component parts in a way that captures both complex objects and para... |

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Citation Context ...nstraint based nature that the translation into Eqlog is so natural. This paper provides a short introduction to Distributed Operational Semantics; a fuller account will be given in a companion paper =-=[15]-=- (in particular, that paper will show that, for certain operational semantics, systems give rise to a topos, whose internal language provides a logic for proving properties of systems' behaviours). Th... |

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Interconnection of object specifications. To appear
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Citation Context ...ion to the hierarchical structure of systems, and provides means of constructing systems from component parts in a way that captures both complex objects and parallel composition with synchronisation =-=[16]-=-. The operational semantics of objects can be very general: for example, a semantics for the object-oriented specification language FOOPS has been given by modelling objects as unlabelled transition s... |