Why Is "Design by Contract" Not More Popular?

Coryoth writes "Design by Contract, writing pre- and post-conditions on functions, seemed like straightforward common sense to me. Such conditions, in the form of executable code, not only provide more exacting API documentation, but also provide a test harness. Having easy to write unit tests, that are automatically integrated into the inheritance hierarchy in OO languages, 'just made sense'. However, despite being available (to varying degrees of completeness) for many languages other than Eiffel, including Java, C++, Perl, Python, Ruby, Ada, and even Haskell and Ocaml, the concept has never gained significant traction, particularly in comparison to unit testing frameworks (which DbC complements nicely), and hype like 'Extreme Programming'. So why did Design by Contract fail to take off?"

Comments

Contracts

[VGPowerlord]

Darl put it best: "Contracts are what you use against parties you have relationships with."

I don't have relationships with random other programmers (even if they are female and cute).

Extreme Programming

[andy314159pi]

I employ what is known as "Extreme Programming." It mostly involves alot of screaming at the monitor and yelling at my coworkers. I get fired alot but I never have a hard time getting a new job with my Extreme Programming skills that I write all over my resume.

Re:Design by contract is 25+ years old

[Waffle Iron]

We call it include files and C coders have been doing it for ages. You noobs and your silly OO languages.

I especially like contractual gems such as:

char *gets(char *s);