9455489 Mead A perusal of current introductory programming texts shows that while the syntax of structured statements is described in formal terms the semantics of structured statement is described in informal verbal terms. The results is that students leave introductory programming courses with a good understanding of the syntactical aspects of structured programming and a poor understanding of the semantical aspects. These programmers will have difficulty assessing either formally of informally the correctness of software which may control critical computer systems. The goal of this project is to develop and assess a programming methodology for the introductory programming sequence, based on a blend of operational and axiomatic semantics, which integrates semantic content (in terms of assertions) into the programming process. A textbook will be written and assessed which presents the methodology. The text will be language-independent and useful either stand-alone or as a supplement to an existing introductory programming text. The impact of this project is on four groups. Instructors of introductory programming courses are able to integrate the semantic-based methodology into their existing courses without changing the primary text: the supplementary text provides them formal support for integrating the methodology. Students learning the methodology via the supplementary text gain more thorough understanding of the program semantics because the semantics are presented formally in terms of assertions. They are better equipped to convince themselves and others that their programs are correct because their programs carry the evidence. Students, instructors, and computing professionals who have not had the advantage of a semantic-based programming methodology will be able to use the text to familiarize themselves with the more formal semantic side of programming. Finally, the public will be long-term beneficiaries of the project. Developers of computer systems whi ch the public depend on will be more confident of the correctness of the systems when they are programmed by students with a sound semantic background, which should result when the methodology is learned.
