Harald Wertz

The squale model — A practice-based industrial quality model

ISO 9126 promotes a three-level model of quality (factors, criteria, and metrics) which allows one to assess quality at the top level of factors and criteria. However, it is difficult to use this model as a tool to increase software quality. In the Squale model, we add practices as an intermediate level between metrics and criteria. Practices abstract away from raw information (metrics, tool reports, audits) and provide technical guidelines to be respected. Moreover, practice marks are adjusted using formulae to suit company development habits or exigences: for example bad marks are stressed to point to places which need more attention. The Squale model has been developed and validated over the last couple of years in an industrial setting with Air France-KLM and PSA Peugeot-Citroën.

Some ideas on the educational use of computers

In this paper we will develop a new point of view on the educational use of computers, stressing its possibility for interactive use and the intellectual implications of the programming activity. After giving a rather detailed analysis of programming viewed as a cognitive process we propose a dual model centered on the notions of piloting and programming, followed by some snapshots of the interaction of a child with a computer. We will end with a proposition for the construction of an intelligent and convivial user environment.

An integrated Lisp programming environment

We are currently implementing a system to help experienced programmers during the development, implementation and debugging of their programs. This system, built on top of a screen oriented structural editor, offers possibilities to attach descriptors to every portion of the program and to maintain - simultaneously - different versions of the program being written, including tentative hypothetical versions. It comprises a mecanism to maintain minimal consistency between modified parts of code, the non-modified parts of code and the attached descriptors, as well as an evaluation module functioning in different modes: normal evaluation, symbolic evaluation and checking evaluation. The standard programming aids, such as indexors, pretty printers, trace packages, undo- and history-facilities are generalized to handle the descriptors and unfinished programs as well

Understanding Lisp Programs is Improving Lisp Programs

In this paper we describe the knowledge and reasoning processes of a special LISP system. In this system completely automatic improvements of both syntactic and semantic features of LISP programs are performed. It is defined as an ordinary LISP system with the following restrictions: exclusion of functional arguments partitioning of variable-, function- and label-names.