When Microsoft announces that it will stop writing code for a month, devoting its attention to a bottom-up review of what it ships now, I hope that every organization is inspired to similar measures.
Reading your current production code and asking, "Why does it do that?" is just the initial goal that may expose a greater challenge. Merely trying to read the code may be instructive. Can you figure out what it does in the first place?
As Kernighan and Plauger observed in their 1978 book, "The Elements of Programming Style," "If youre as clever as you can be when you write it, how will you ever debug it?" Sitting down for a spell of code reading may elicit uncomfortable discoveries as to how clever you have been in the past—and how much more clever you may need to become.
Java guru Ian McFarland, president of Neo Ventures, in Santa Monica, Calif., offers a readability criterion that many coders share: "If a method is too big to fit on one page of screen, its too long. If you dont read it and go, Yeah, that makes sense, its too complex. Simplify."
I feel this way, not just about methods in code but about entire systems. If you cant describe the overall function of the system on the proverbial 3-by-5-inch index card, how can you begin the process of top-down decomposition that leads to understandable specifications and maintainable implementations?
You can build something that works, even if it doesnt make sense, but it will take longer to build, and it may be impossible to fix. As Microsofts Anders Hejlsberg said at the launch of Visual Studio .Net, to appreciative coder laughter, "It used to be that all we could do was list thousands of Windows entry points in alphabetical order. Now, theres a name space: When you want to do something, you know where to look." (Ill add that you may need to read other things than code: Do your paper forms capture data correctly?)
Take the time to look around, as well as inside your systems, and think about what you want them to do.
Tell me what your reading uncovers at [email protected]