Many tools designed to help programmers view and manipulate source code exploit the formal structure of the programming language. Language-based tools use information derived via linguistic analysis to offer services that are impractical for purely text-based tools. In order to be effective, however, language-based tools must be designed to account properly for the documentary structure of source code: a structure that is largely orthogonal to the linguistic but no less important. Documentary structure includes, in addition to the language text, all extra-lingual information added by programmers for the sole purpose of aiding the human reader: comments, white space, and choice of names. Largely ignored in the research literature, documentary structure occupies a central role in the practice of programming. An examination of the documentary structure of programs leads to a better understanding of requirements for tool architectures.

Abstract. The use of formal methods can significantly improve software quality. However, many instructors and students consider formal methods to be too difficult, impractical, and esoteric for use in undergraduate classes. This paper describes a method, used successfully at several universities, that combines ninja stealth with the latest advances in formal methods tools and technologies to integrate applied formal methods into software engineering courses. 1 Enter the Ninja Software development tools and techniques based on formal methods hold great promise for improving software quality. Unfortunately, many undergraduate computer science and software engineering curricula include no formal methods instruction beyond the introduction of basic concepts such as the assertion and the loop invariant. Moreover, even when formal methods concepts are introduced, they tend not to be used outside of toy examples. Many students and instructors, it seems, believe that the very words “formal methods ” imply writing equations

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