We Don't Need No Stinking Comments

I am trying to put together some coding standards for the company where I currently work. Yeah, another exercise, but not (I hope) a futile one. As always happens, someone wanted to have a standard for comments.

My only answer to that was this: "If a program acts differently from the way the end-documentation says it should, which do you trust?" I feel the same way about comments. It's not that I don't appreciate them, but I just don't trust them as much as I trust the code. Admittedly it's usually a harder slog through the code, but once you've figured out what the code does, the comments are usually not useful.

As Kernighan and Plauger say on page 142 (1974 edition) of "The Elements of Programming Style:"

The problem with comments that do not accurately reflect the code is that they may well be believed subconsciously, so the code itself is not examined critically.

I wish I could come up with some good way to measure the effectiveness (or in-effectiveness) of comments, but I'm just going to have to go with my gut on this one. I don't think we can have any standard for comments that anyone will agree upon. We may be able to come up with some recommendations, but as for enforceable standards? In "The Practice of Programming" (Kernighan and Pike, 1999), page 24 generously says:

Comments can be useful, of course.

And the rest of the page goes on to show some good usages. This page, however, is surrounded by a list of things NOT to do with comments. Seems like it's easier to tell people what not to do, rather than what to do.

[If you don't know the American pop culture reference from the title, check here or here.]