Memento as a programming model: I was talking to Mark English as the movie Memento. The main character can't create or store long-term memories as the result of a violent accident. The movie proceeds from the end and moves backward (and forward). This has the effect of the viewer experiencing reality in the same way as someone with impaired memory. The amazing thing is that the main character has to live out his life without knowing what's just happened, and he's developed a variety of strategies and habits to get by, such as tattooing his body with key messages about the murder of his wife.

Anyway, it occurred to me that "lack of memory" is closely related to "good programming practice." Imagine if every day you had to work on a program, you forgot the prior day's coding!

• You'd develop simplifying habits: simple variable names, variable names that hint at their type.

• You're code would be well broken down. No function or class that couldn't be understood in 15 minutes.

• You'd document it first then fill in the details. You'd need to concisely capture a description of the problems being solved.

• You'd write test code before even starting on the code. The first thing you'd do every day after re-reading the documentation would be to run the unit test to know if you were done yet.

• Versions would be checked in often. You would naturally save it once you started forgetting parts.

Well, I realize it's a tenuous sort of argument. I probably couldn't program with limited memory. Some of the best programmers I know, or have heard of, have tremendously strong memory. James Tanis tells me that Seth Robertson was able to do some of his best kernel work because he could keep so much of it in his head at once. Nevertheless, it's a fascinating metric for judging good programming practice. If there's a question of how to program something, ask yourself what someone without long-term memory would do.

Where was I?