Robert Martin

Back in my days working in the Bell Labs Software Production Research organization (Production, indeed!) we had some back-of-the-envelope findings that suggested that consistent indentation style was one of the most statistically significant indicators of low bug density. We want it to be that architecture or programming language or some other high notion should be the cause of quality; as people whose supposed professionalism owes to the mastery of tools and lofty design methods, we feel insulted by the value that those factory-floor machines, the coders, add through the simple consistent application of an indentation style.

In our profession, we desperately need all the help we can get. If a clean shop floor reduces accidents, and well-organized shop tools increase productivity, then I’m all for them.

Clean code always looks like it was written by someone who cares. There is nothing obvious that you can do to make it better. All of those things were thought about by the code’s author, and if you try to imagine improvements, you’re led back to where you are, sitting in appreciation of the code someone left for you—code left by someone who cares deeply about the craft.

None of these different schools is absolutely right. Yet within a particular school we act as though the teachings and techniques are right. After all, there is a right way to practice Hakkoryu Jiu Jitsu, or Jeet Kune Do. But this rightness within a school does not invalidate the teachings of a different school.

As we’ll see later on, even if the container is a List, it’s probably better not to encode the container type into the name.

the developer is likely to pick an object by name without seeing your copious comments or even the list of methods supplied by that class.

In one case the author of the code suggested using a different font so that the differences were more obvious, a solution that would have to be passed down to all future developers as oral tradition or in a written document

Imagine that you have a Product class. If you have another called ProductInfo or ProductData, you have made the names different without making them mean anything different. Info and Data are indistinct noise words like a, an, and the.

Noise words are redundant. The word variable should never appear in a variable name. The word table should never appear in a table name. How is NameString better than Name? Would a Name ever be a floating point number? If so, it breaks an earlier rule about disinformation. Imagine finding one class named Customer and another named CustomerObject. What should you understand as the distinction?

In the absence of specific conventions, the variable moneyAmount is indistinguishable from money, customerInfo is indistinguishable from customer, accountData is indistinguishable from account, and theMessage is indistinguishable from message. Distinguish names in such a way that the reader knows what the differences offer.