Flemming Nielson – författare

The authors describe here a framework in which the type notation of functional languages is extended to include a notation for binding times (that is run-time and compile-time) that distinguishes between them. Consequently the ability to specify code and verify program correctness can be improved. Two developments are needed, the first of which introduces the binding time distinction into the lambda calculus, in a manner analogous with the introduction of types into the untyped lambda calculus. Methods are also presented for introducing combinators for run-time. The second concerns the interpretation of the resulting language, which is known as the mixed lambda-calculus and combinatory logic. The notion of 'parametrized semantics' is used to describe code generation and abstract interpretation. The code generation is for a simple abstract machine designed for the purpose; it is close to the categorical abstract machine. The abstract interpretation focuses on a strictness analysis that generalises Wadler's analysis for lists.

The authors describe here a framework in which the type notation of functional languages is extended to include a notation for binding times (that is run-time and compile-time) that distinguishes between them. Consequently the ability to specify code and verify program correctness can be improved. Two developments are needed, the first of which introduces the binding time distinction into the lambda calculus, in a manner analogous with the introduction of types into the untyped lambda calculus. Methods are also presented for introducing combinators for run-time. The second concerns the interpretation of the resulting language, which is known as the mixed lambda-calculus and combinatory logic. The notion of 'parametrized semantics' is used to describe code generation and abstract interpretation. The code generation is for a simple abstract machine designed for the purpose; it is close to the categorical abstract machine. The abstract interpretation focuses on a strictness analysis that generalises Wadler's analysis for lists.

Both functional and concurrent programming are relatively new paradigms with great promise. In this book, a survey is provided of extensions to Standard ML, one of the most widely used functional languages, with new primitives for concurrent programming. Computer scientists and graduate students will find this a valuable guide to this topic.

Semantics will have an important role to play in the future development of software systems and domain specific languages, and there is a real need for an introductory book that presents the fundamental ideas behind these approaches; stresses their relationship by formulating and proving the relevant theorems; and illustrates the applications of semantics in computer science. This book investigates the relationship between the various methods and describes some of the main ideas used, illustrating these via interesting applications. Historically important application areas are used together with some exciting potential applications including: Validating prototype implementations of programming languages. Verifying program analyses that are part of more advanced implementations of programming languages. Verifying security analyses. Verifying useful program properties including information about execution time.

Concurrent and distributed processes occur everywhere: in embedded systems, in information networks and databases, and in the form of applets roaming around on the World-Wide-Web. This book presents and develops state-of-the-art validation techniques for detecting safety violations; the focus is on the correctness of techniques that suffice for fully automatic validation of key components of such systems. It builds on and extends the notion of types, popular in many sequential programming languages as a technique for catching certain kinds of errors already at program development time, by incorporating behaviours (or structured effects) that are able to track the information flow in the presence of procedures, channel based communication, and the dynamic creation of network topologies. The technical development is performed for a language based on Concurrent ML.

This textbook is an introduction to the use of formal methods ranging from semantics of key programming constructs to techniques for the analysis and verification of programs. The authors use program graphs as the mechanism for representing the control structure of programs in order to find a balance between generality and conceptual complexity.The early chapters on program graphs and the Guarded Commands language are sufficient introduction for most readers to then enjoy a plug-and-play approach to the remaining chapters. These explain formal methods for analysing the behaviour of programs in various ways ranging from verification, via program analysis and language-based security, to model checking. The remaining chapters present language extensions with procedures and concurrency and cover their semantics.The book is suitable for advanced undergraduate and graduate courses in software development, and the text is supported throughout with exercises of varying grades of difficulty. The authors have developed an online learning environment that allows students to create examples beyond those covered in the main text, and in the book appendices they present programming projects aimed at implementing central parts of the development using the functional language F#.

This open access book constitutes the proceedings of the 8th International Conference on Principles of Security and Trust, POST 2019, which took place in Prague, Czech Republic, in April 2019, held as part of the European Joint Conference on Theory and Practice of Software, ETAPS 2019.

Program analysis concerns static techniques for computing reliable approximate information about the dynamic behaviour of programs. Applications include compilers (for code improvement), software validation (for detecting errors in algorithms or breaches of security) and transformations between data representation (for solving problems such as the Y2K problem). This book is unique in giving an overview of the four major approaches to program analysis: data flow analysis, constraint based analysis, abstract interpretation, and type and effect systems. The presentation demonstrates the extensive similarities between the approaches; this will aid the reader in choosing the right approach and in enhancing it with insights from the other approaches. The book covers basic semantic properties as well as more advanced algorithmic techniques. The book is aimed at M.Sc. and Ph.D. students but will be valuable also for experienced researchers and professionals.

This book constitutes the thoroughly refereed post-conference proceedings of the 4th International Symposium on Trustworthy Global Computing, TGC 2008 held in Barcelona, Spain, in November 2008. The 12 revised papers presented together with one invited paper were carefully selected from 26 submissions during two rounds of reviewing and improvement. The TGC 2008 symposium papers focus on providing tools and frameworks for constructing well-behaved applications and for reasoning about their behavior and properties in models of computation that incorporate code and data mobility over distributed networks with highly dynamic topologies and heterogeneous devices.