Students shall get an overview of type systems in programming languages and learn about their pros and cons. Especially the potentialities and limits in the practical use of types shall be shown. The focus is on types on modern object-oriented programming languages.

Meaning of the notion of type in programming languages, classification of programming languages regarding type systems, simple theoretical type models, types in imperative languages (especially Ada), theoretical models of polymorphic type systems and type inference, programming languages with polymorphic type systems, subtyping, genericity, types as partial specifications of object behariour, use of polymorphic type systems in object-oriented programming.

Educational Concept:

"Typesystems" is a lecture in the classic style based on a weekly talk. First we give an overview and introduce some terminology. Then, we (1) discuss practical experiences in subtopics, (2) introduce formal models and (3) show typical applications thereof, leading to new practical experiences. We repeat this cycle several times, thereby increasing the complexity with each iteration. In the last part of the lecture we discuss trends and approaches to address current problems.

ECTS-Breakdown:

• 1 ECTS: Weekly lectures
• 1 ECTS: Consolitation of the topics by autonomous research
• 1 ECTS: Preparation for exam and oral exam

By interview.

Interviews can be taken each Monday (11 to 12, except during holydays), at the last course date and by negotiation.

Lecture notes for this course are available. See http://www.complang.tuwien.ac.at/franz/typsysteme.html

Good practical programming capabilities in strongly typed languages as well as knowledge about the static use of types are required.