Communications of the ACM

last byte

I M A G E B Y D A V I D M O N N I A U X

we knew about program correctness. Design by Contract is a transposition to software of concepts that everyone is familiar with. If I want to buy something from you, I have a certain set of obligations to satisfy, and on your side, you also have obligations. Your obligations map into my benefits and conversely. So, too, with preconditions and postconditions in software.

Let’s talk about your move to ETH Zu-
rich, where you’ve been since 2001.

It was not planned, but it has worked out very nicely. In 2000,

Niklaus
actually ahead of the curve. So coming
back from Portland, we refocused the
company on Eiffel.

You are also known for the idea of “ Design by Contract,” a method of assuring a program’s correctness by specifying the conditions that each element must satisfy; there are preconditions, which state what an operation expects, and postconditions, which state what an operation guarantees. Did that idea evolve in tandem with Eiffel?

Yes. After reading the works of Hoare and Dijkstra, it seemed like a direct, practical application of everything

FRENCH-BORN COMPUTER SCIENTIST Bertrand Meyer—best known as an early advocate of object-oriented programming techniques and creator of the programming language and environment Eiffel—has enjoyed a varied career in industry and academia. Currently a professor of software engineering at ETH Zurich, the Swiss Federal Institute of Technology, he also has worked at Électricité de France (EDF) and at the University of California, Santa Barbara, and he continues to serve as CEO and chief architect at the California-based company he founded in 1985, Eiffel Software.

After receiving degrees from Stanford and the University of Nancy, you spent nearly 10 years in industry at Électricité de France (EDF). When did you begin working on Eiffel, the object-oriented language and environment that you continue to refine and develop?

In 1983, I got to spend a sabbatical at the University of California, Santa Barbara. A Japanese company got excited about a structured editor we had developed, and in 1985, we decided to found a company that’s now called Eiffel Software.

We were looking for a programming language. We didn’t like what was available, so I designed a notation that became Eiffel. Initially, I didn’t pay much attention to it. But in 1986, we attended the first OOPSLA ( Object-Oriented Programming, Systems, Languages, and Applications) conference in Portland, and that’s where we realized that what I thought obvious was

DOI: 10.1145/2716347 Leah Hoffmann
Q&A
Object Lessons
The creator of the Eiffel programming language discusses his career
in industry and academia, “Design by Contract,” and his views on
Agile software development.