Sunday, April 6, 2008

You're turning into a dinosaur

If your workload consists entirely of short-term assignments that don't develop your skills, be dissatisfied. If you're working in a competitive software market, half of what you now need to know to do your job will be out of date in three years. If you're not learning, you're turning into a dinosaur.

The Humble Programmer

At the 1972 Turing Award Lecture, Edsger Dijkstra delivered a paper titled "The Humble Programmer." He argued that most of programming is an attempt to compensate for the strictly limited size of our skulls. The people who are best at programming are the people who realize how small their brains are. They are humble. The people who are the worst at programming are the people who refuse to accept the fact that their brains aren't equal to the task. Their egos keep them from being great programmers. The more you learn to compensate for your small brain, the better a programmer you'll be. The more humble you are, the faster you'll improve.

Thursday, April 3, 2008

Logical cohesion vs Event handler

Logical cohesion occurs when several operations are stuffed into the same routine and one of the operations is selected by a control flag that's passed in. It's called logical cohesion because the control flow or "logic" of the routine is the only thing that ties the operations together—they're all in a big if statement or case statement together.

Event Handler: the routine's only function is to dispatch commands and it doesn't do any of the processing itself, that's usually a good design. The technical term for this kind of routine is "event handler." An event handler is often used in interactive environments such as the Apple Macintosh, Microsoft Windows, and other GUI environments.

Tuesday, April 1, 2008

Operating-room technique

Data is sterilized before it's allowed to enter the operating room. Anything that's in the operating room is assumed to be safe. The key design decision is deciding what to put in the operating room, what to keep out, and where to put the doors—which routines are considered to be inside the safety zone, which are outside, and which sanitize the data. The easiest way to do this is usually by sanitizing external data as it arrives, but data often needs to be sanitized at more than one level, so multiple levels of sterilization are sometimes required.