SHF: Small: Collaborative Research: Online Verification-Validation

越来越多的网络上的现代软件具有丰富的可扩展性，加速了它的发展，并大大缩短了开发和部署之间的时间。这项研究的智力价值在于挑战了在创建可扩展的软件（易于重用和扩展）和正确的软件（满足其规范）之间的错误选择。这项工作提出的新方法，增量验证-确认，通过提供一个框架，使这些规程作为可执行代码精确而有效地进行交流，使程序员能够将特定于领域的安全规程引入可扩展系统。该项目更广泛的意义和重要性在于改变了程序员为web构建正确的可扩展软件的方式。这项研究的目标是ECMAScript (JavaScript)，使这项研究能够对创建和使用JavaScript的大量语言和系统产生直接影响。此外，该项目代表了科罗拉多大学和马里兰大学之间的新合作，将验证、增量计算和运行时系统方面的专家聚集在一起。最后，该项目有利于参与院校的研究生和本科生教学任务，因为项目的各个方面丰富了程序分析和编程语言课程。增量验证—验证鼓励程序员与可执行规范共同设计他们的系统，这些规范在系统执行时动态地检查这些系统。此外，与动态和非增量执行的典型断言不同，所提出的断言服从于增强其性能的新模式：在回归验证中，验证部分取消一些检查，用剩余版本动态重写程序；在渐进式验证中，在线验证发生在每个缓存和重用工作的过程中，以避免对从早期的过程中仍然存在的事实进行从头验证。最后，为了避免迫使分析程序员在他们创建的每个分析中显式地推断增量更改，元层使用隐式增量元语言隐式地表达增量计算，其抽象隐藏了基于每个更改的推理。

Increasingly, modern software on the web is richly extensible, accelerating its evolution and dramatically reducing the time between development and deployment. The intellectual merit of this research consists of challenging the false choice between creating software that is extensible (easy to reuse and extend) and software that is correct (meets its specifications). The new approach advanced by this work, Incremental Verification-Validation, enables programmers to bring domain-specific safely disciplines to extensible systems, by providing a framework where these disciplines are communicated both precisely and usefully, as executable code. The project's broader significance and importance consist in changing the way programmers approach building correct extensible software for the web. The research targets ECMAScript (JavaScript), enabling this research to have a direct impact on the vast number of languages and systems that create and use JavaScript. Further, the project represents a new collaboration across the University of Colorado and University of Maryland, bringing together experts across verification, incremental computing, and runtime systems. Finally, this project benefits the graduate and undergraduate teaching mission at the participating universities, as aspects of the project enriches the program analysis and programming language courses.Incremental Verification-Validation encourages programmers to co-design their systems with executable specifications that check these systems dynamically, as they execute. Moreover, unlike typical assertions, which execute dynamically and non-incrementally, the proposed are subject to novel patterns that enhance their performance: In regressive validation, verification partially discharges some checks, dynamically rewriting the program with residual versions; in progressive verification, online verification occurs in passes that each cache and reuse work, to avoid from-scratch verification of facts that still hold from earlier passes. Finally, to avoid forcing analysis programmers to reason about incremental changes explicitly in each analysis that they create, the meta layer expresses incremental computations implicitly, using an implicitly-incremental meta language whose abstractions hide reasoning on a per-change basis.