Do Programmers Actually Use Assertions?

P.Chalin queries: "Do programmers actually use assertions (like the assert statement of various programming languages)? If so, what should be done when errors or exceptions are raised during the evaluation of an assertion? I am collecting opinions and stats via a short questionnaire. Thanks."

Comments

(Disabled) assertions suck.

[Dr. Bent]

Assertions (usually) are a preversion of the failfast principle, because they can be turned off. For the same reason you can't fit a 120v plug in a 240v outlet, error checking in software should be a permanent and reliable function of the design of the system.

Either your software is broken, or it isn't. If it is, you (and the users) need to know about it as soon as possible to prevent little errors from causing big errors.

Now, if you want to have an assertion that cannot be disabled, and is basically just syntax sugar for if(condition) throw new SomeException();, that could be useful. But exceptions that can be disabled only lead to a false sense of security.

Yes, look into GCC

[norwoodites]

Yes and in fact if you look into GCC there is more checking code than most people think because most of the time in a released compiler these checks are not enabled. (--disable-checking). In fact in some cases even on the main development some checking is not enabled by default because it just take so long (like 5 days) to just bootstrap the compiler. I am taking about gcac checking. Also RTL checking takes a long time too.

--enable-checking=assert,fold,gc,gcac,misc,rtlfl ag ,rtl,tree is fun as it takes 5 days to build a compiler even on a fast computer.

Re:They drive me nuts

[miu]

Assertions do not detect runtime errors, they do not even detect incorrect assumptions about data formating, they detect programming errors. An assertion is a statement you make what the state of some portion of the program at that point, if the library is asserting on you then either the assert (and the library itself) is wrong or your use of the library is wrong, either way the assert has done exactly what it was supposed to do - alerted you to a programming error.