Wishes for object-oriented languages

Abstract

For a long time, I have liked to compare the parameter-passing modes of Algol 60 (some of you are probably old enough to remember) with speakers at scientific conferences. Namely, call by value vs. call by name in Algol, and authors of regular papers vs. invited speakers at conferences. This time I am lucky enough to be in the latter category; I also used to say that these are sometimes people who can no more make enough new contribution to have good chances with reviewers and programme committees. After this session, we will listen for about two full days to sophisticated technical presentations that will require the utmost concentration to be well understood. In contrast, some lighter entertainment may be quite appropriate in an invited talk. One reason for the lightness is that I could not allocate as much time for preparing the talk as I would have wished. This distributed printed version of the talk does not even contain complete bibliographic references. I hope my Finglish will not be too hard to be understood by speakers of Frenglish. Today, the emphasis of research and development in object-oriented software engineering has moved from classes, methods and other base-level entities to components, frameworks and other larger entities. Consequently, interests have also moved from programming languages to environments and tools for manipulating these entities. This evolution is natural and welcome, but it does not mean that the existing object-oriented programming languages are already perfect and no further progress on that level is needed. I will present several things that I would wish to be improved in current languages or their successors. Very little of what I am going to say will be really new, but some points are probably not so well known, or are often forgotten. I have mentioned many of them in my course on OOP at the university (if you want to have my lecture notes in Finnish, feel free to ask). In my papers, I have liked to write about the darker side of things, especially C++, but this time I am speaking about wishes; of course, it is essentially the same approach, but labelled in am more positive and polite way. I will not be as satirical as Bertrand Meyer in his pamphlet “UML, the positive spin” — which I hope many of you have seen. Several of my wishes are controversial, and I will be happy if they stimulate discussion. Very likely, many of the wishes have also been fulfilled in some OO languages that I don’t know, at least not well enough to have noticed. Please comment on such items, too. My research interests have always been mainly in statically typed languages (STOOPLs). This is therefore assumed in most parts of the talk; however, there are things that are rele-