物件導向軟體之架構(Object-Oriented Software Construction)探討

A type system is a syntactic method for automatically checking the absence of certain erroneous behaviors by classifying program phrases according to the kinds of values they compute. The study of type systems -- and of programming languages from a type-theoretic perspective -- has important applications in software engineering, language design, high-performance compilers, and security.This text provides a comprehensive introduction both to type systems in computer science and to the basic theory of programming languages. The approach is pragmatic and operational; each new concept is motivated by programming examples and the more theoretical sections are driven by the needs of implementations. Each chapter is accompanied by numerous exercises and solutions, as well as a running implementation, available via the Web. Dependencies between chapters are explicitly identified, allowing readers to choose a variety of paths through the material.The core topics include the untyped lambda-calculus, simple type systems, type reconstruction, universal and existential polymorphism, subtyping, bounded quantification, recursive types, kinds, and type operators. Extended case studies develop a variety of approaches to modeling the features of object-oriented languages.

https://www.seas.upenn.edu/~bcpierce/tapl/contents.pdf

Types and Programming Languages

Program analysis utilizes static techniques for computing reliable information about the dynamic behavior of programs. Applications include compilers (for code improvement), software validation (for detecting errors) and transformations between data representation (for solving problems such as Y2K). This book is unique in providing 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 illustrates the extensive similarities between the approaches, helping readers to choose the best one to utilize.

Principles of program analysis

We design a novel, communication-efficient, failure-robust protocol for secure aggregation of high-dimensional data. Our protocol allows a server to compute the sum of large, user-held data vectors from mobile devices in a secure manner (i.e. without learning each user's individual contribution), and can be used, for example, in a federated learning setting, to aggregate user-provided model updates for a deep neural network. We prove the security of our protocol in the honest-but-curious and active adversary settings, and show that security is maintained even if an arbitrarily chosen subset of users drop out at any time. We evaluate the efficiency of our protocol and show, by complexity analysis and a concrete implementation, that its runtime and communication overhead remain low even on large data sets and client pools. For 16-bit input values, our protocol offers $1.73 x communication expansion for 210 users and 220-dimensional vectors, and 1.98 x expansion for 214 users and 224-dimensional vectors over sending data in the clear.

https://dl.acm.org/doi/pdf/10.1145/3133956.3133982

Practical Secure Aggregation for Privacy-Preserving Machine Learning

Domain-specific languages (DSLs) are languages tailored to a specific application domain. They offer substantial gains in expressiveness and ease of use compared with general-purpose programming languages in their domain of application. DSL development is hard, requiring both domain knowledge and language development expertise. Few people have both. Not surprisingly, the decision to develop a DSL is often postponed indefinitely, if considered at all, and most DSLs never get beyond the application library stage.Although many articles have been written on the development of particular DSLs, there is very limited literature on DSL development methodologies and many questions remain regarding when and how to develop a DSL. To aid the DSL developer, we identify patterns in the decision, analysis, design, and implementation phases of DSL development. Our patterns improve and extend earlier work on DSL design patterns. We also discuss domain analysis tools and language development systems that may help to speed up DSL development. Finally, we present a number of open problems.

/pdf/when-and-how-to-develop-domain-specific-languages-29nvxv3ngp.pdf

When and how to develop domain-specific languages

Introduction Algebraic speciications can be used for the speciication of var

The ASF+SDF Meta-environment: Documentation Tools for Free!

We present a new approach to inferring types in untyped object-oriented programs with inheritance, assignments, and late binding. It guarantees that all messages are understood, annotates the program with type information, allows polymorphic methods, and can be used as the basis of an optimizing compiler. Types are finite sets of classes and subtyping is set inclusion. Using a trace graph, our algorithm constructs a set of conditional type constraints and computes the least solution by least fixed-point derivation.

/pdf/object-oriented-type-inference-14444u5kgt.pdf

Object-Oriented Type Inference

Most unary relational database operators can be described through functions from tuples to tuples. Injectivity of the specified function ensures that no duplicates are created in the relational result. This normally reduces the complexity of the query from O(r log r) to O(r), where r is the number of tuples in the argument relation. We consider functions obtained as terms over a general signature. The semantic properties of the operators are specified by Horn clauses generalizing functional dependencies. Relative to such specifications, we present an optimal algorithm for detecting injectivity of unary queries. The complexity of this algorithm is linear in the size of the query. It turns out that relational functional dependencies are very easily incorporated into this framework. As a further result, we provide a Horn clause characterization of the functional dependencies that can be propagated to the result relation.

https://tidsskrift.dk/daimipb/article/download/6702/5819

Optimal detection of query injectivity

Type Inference for Turbo Pascal.

A system of hierarchical, imperative, fully recursive types allows program fragments written for small types to be reused for all larger types. To exploit this property to enable type-safe hierarchical procedures, it is necessary to impose a static requirement on procedure calls. We introduce an example language and prove the existence of a sound requirement which preserves static correctness while allowing hierarchical procedures. This requirement is further shown to be optimal , in the sense that it imposes as few restrictions as possible. This establishes the theoretical basis for a very powerful and general type hierarchy with static type checking, which enables 1st order polymorphism and (multiple) inheritance in a language with assignments.

/pdf/static-correctness-of-hierarchical-procedures-4ultubhnfg.pdf

Michael I. Schwartzbach

Papers

The ASF+SDF Meta-environment: Documentation Tools for Free!

Object-Oriented Type Inference

Optimal detection of query injectivity

Type Inference for Turbo Pascal.

Static Correctness of Hierarchical Procedures