C++中继承机制的语义剖析

面向对象编程语言的语义是目前面向对象技术中研究的重点之一,而其中继承机制的语义研究尤为重要.文章主要分析了C++语言中公有派生、私有派生和对象成员的语义,并且给出了这些语义的联系和区别.特别指出的是,在对象成员和私有派生都可用的情况下,尽可能用对象成员实现.     

C＋＋中继承机制的语义剖析

面向对象编程语言的语义是目前面向对象技术中研究的重点之一，而其中继承机制的语义研究尤为重要。文章主要分析了C 语言中公有派生、私有派生和对象成员的语义，并且给出了这些语义的联系和区别。特别指出的是，在对象成员和私有派生都可用的情况下，尽可能用对象成员实现。     

Towards Verification of C Programs: Axiomatic Semantics of the C-kernel Language

With the aim of the verification of programs in the C-light language [1], its kernel C-kernel is separated, and an axiomatic semantics for it is suggested. A theorem on soundness of the axiomatic semantics of C-kernel with respect to its operational semantics is proved. The C-light language is used as an input language of the program verification system, which includes a translator to C-kernel and a generator of the correctness conditions for C-kernel programs, which is based on its axiomatic semantics.     

A Formal Semantics for the SmartFrog Configuration Language

System configuration languages are now widely used to drive the deployment and evolution of large computing infrastructures. Most such languages are highly informal, making it difficult to reason about configurations, and introducing an important source of failure. We claim that a more rigorous approach to the development and specification of these languages will help to avoid these difficulties and bring a number of additional benefits. In order to test this claim, we present a formal semantics for the core of the SmartFrog configuration language. We demonstrate how this can be used to prove important properties such as termination of the compilation process. To show that this also contributes to the practical development of clear and correct compilers, we present three independent implementations, and verify their equivalence with each other, and with the semantics. Supported by an extended example from a real configuration scenario, we demonstrate how the process of developing the semantics has improved understanding of the language, highlighted problem areas, and suggested alternative interpretations. This leads us to advocate this approach for the future development of practical configuration languages.     

A Formal Semantics for DAI Language NUML

1IntroductionAsE.H.Durfeestatesin[1]:Artificia1Inte1ligence(AI)hasemphasizedbuilding"stand-alonesystems"thatcansolveproblemswithminimalhelpfromothersystems(computerorman).Thesesystemshavetraditionallybeenbrittle,inthesensethattheyfailmiser-ablywhenpresentedwithproblemsevens1ightlyoutsideoftheir1imitedrangeofexpertise...Amorepowerful,extensiblestrategyforovercomingtheinherentboundsofintelligencepresentinanyfilliteAI(ornaturaI)systemistoputsysteminasocietyofsystems,sothatitcandrawonadiversec…     

Towards Verification of C Programs. C-Light Language and Its Formal Semantics

The C-light language is described, which is a representative subset of C. C-light permits deterministic expressions, limited use of switch and goto statements, and, instead of library functions for work with dynamic memory, includes C++ statements new and delete. A survey of structured operational semantics of the C-light language in Plotkin's style is given.     

Semantics for a Quantum Programming Language by Operator Algebras

This paper presents a novel semantics for a quantum programming language by operator algebras, which are known to give a formulation for quantum theory that is alternative to the one by Hilbert spaces. We show that the opposite of the category of W*-algebras and normal completely positive subunital maps is an elementary quantum flow chart category in the sense of Selinger. As a consequence, it gives a denotational semantics for Selinger’s first-order functional quantum programming language. The use of operator algebras allows us to accommodate infinite structures and to handle classical and quantum computations in a unified way.     

Formalism and Language Tools for Specification of the Semantics of Software Libraries

The paper considers the specification of the structure and the behavior of software libraries. It describes the existing problems of library specifications. A brief overview of the research field concerned with formalizing the specification of libraries and library functions is presented. The requirements imposed on the formalism designed are established; the formalism based on these requirements allows specification of all the properties of the libraries needed for automation of several classes of problems: defect detection in software, migration of applications into a new environment, and generation of software documentation. Requirements for language tools based on the developed formalism are proposed. The conclusion defines potential directions for further research.     

PETRI网描述的VPML语义

企事业过程建模系统EPMS（Enterprise Process Modeling System）以可视化过程建模语言VPML（Visual Process Modeling Language）为基础,用于过程模型建造和过程模型模拟。VPML语义的正确性与完备性是得到可靠的过程模型的基本保证。文章以枚举法为基础,利用PETRI网描述VPML的所有语义,证明其语义的正确性与完备性。利用二者之间建立的映射关系,将VPML建立的模型转换为PETRI网描述,借助于PETRI网工具可进行系统性能分析,提高产品开发的可靠性。     

Algebraic Semantics of an Imperative Programming Language

Programming and Computer Software -     

Compositional Operational Semantics of a UML-Kernel-Model Language

We define a compositional operational semantics for state machines and their composition in UML. Each state machine describes the behavior of an object of a class. If a class of a newly generated object is active, a new activity group, which is a singly-threaded collection of objects, is generated. Communication of state machines between activity groups differs from the one inside an activity group. We introduce (i) two parallel combinators reflecting this difference, which return a SOS given that their arguments are SOS, (ii) an SOS for each state machine regarded in isolation.     

命令式模糊程序语言的语义

文中关注计算机语言的形式语义学,旨在建立一种命令式模糊程序语言的指称语义与最弱(线性)前置条件语义.首先,借助模糊逻辑中的三角模、三角余模、非、蕴含以及模糊关系的合成等成功地完成了这两种语义的建模.这种方法为形式语义学的研究提供了一个新的视角.其次,证明了该语言的一些重要性质并讨论了最弱前置条件语义与最弱线性前置条件语义之间的关系.最后,证明了指称语义与最弱(线性)前置条件语义之间的对偶,该对偶表明了这两种语义可以相互诱导.     

A Semantics for Static Type Inference in a Nondeterministic Language

Plotkin used the models of reduction in order to obtain a semantic characterization of static type inference in the pure λ-calculus. Here we apply these models to the study of a nondeterministic language, obtaining results analogous to Plotkin′s.     

Towards an Independent Semantics and Verification Technology for the HLPSL Specification Language

We present an algorithm for the translation of security protocol specifications in the HLPSL language developed in the framework of the AVISPA project to a dialect of the applied pi calculus. This algorithm provides us with two interesting scientific contributions: at first, it provides an independent semantics of the HLPSL specification language and, second, makes it possible to verify protocols specified in HLPSL with the applied pi calculus-based ProVerif tool. Our technique has been implemented and tested on various security protocols. The translation can handle a large part of the protocols modelled in HLPSL.     

Some Remarks on the Semantics of FIPA's Agent Communication Language

The Foundation for Intelligent Physical Agents (FIPA) standardisation body has produced a set of specifications outlining a generic model for the architecture and operation of agent-based systems. The FIPA'97 Specification Part 2 is the normative specification of an Agent Communication Language (ACL) which agents use to talk to each other. The FIPA ACL is based on speech act theory. Its syntax is defined by performatives parameterised by attribute value pairs, while its semantics is given in terms of the mental states of the communicating agents (i.e. intentionality). However, it is not clear if the formal semantics is meant as a normative or informative specification. The primary purpose of this paper is then to give an expository analysis of the FIPA ACL semantics to clarify this situation. We also offer some guidelines motivated from our own analysis, experience and understanding of how the semantic definitions and logical axioms should be interpreted and applied. However, our conclusion is that while the FIPA ACL specification offers significant potential to a developer using it for guidance, there are limitations on using an agent's mental state to specify the meaning of a performative as part of a normative standard. We consider some possibilities for making improvements in this direction.     

Winskel is (almost) Right: Towards a Mechanized Semantics Textbook

We present a formalization of the first 100 pages of Winskel's textbook The Formal Semantics of Programming Languages in the theorem prover Isabelle/HOL: 2 operational, 2 denotational, 2 axiomatic semantics, a verification condition generator, and the necessary soundness, completeness and equivalence proofs, all for a simple imperative programming language. Received March 1997 / Accepted in revised form June 1998     

基于逻辑的软件演化操作语言及结构化操作语义

由于使用环境和新技术的不断变化,软件演化的控制变得日趋复杂.为了提高软件演化活动的可视化和形式化支持程度,结合谓词逻辑和软件演化,提出了一种软件演化操作语言SEOL(Software Evolution Operational Language)描述软件演化,给出了SEOL的语法和结构化操作语义描述,并指出了软件演化操作语义等价分析方法.结合软件代码演化和软件模型演化实例,说明了SEOL的应用.与已有的软件演化操作描述相比,SEOL在易用性、可重用性和形式化分析方面有明显的改善,为软件演化的管理、分析和实施奠定了基础.