The best way I know to debug a piece of software (or just to understand it) is to rewrite it. I keep and rewriting it until a) the error presents itself or b) I

The best way I know to debug a piece of software (or just to understand it) is to rewrite it. I keep and rewriting it until a) the error presents itself or b) I have interiorized the model so profoundly that I can understand where the problem is. Of course I am a big fan of automated tests.