As the old adage goes, "an ounce of prevention is worth a pound of cure", and it's especially pertinent when it comes to software bugs. The first two questions

As the old adage goes, "an ounce of prevention is worth a pound of cure", and it's especially pertinent when it comes to software bugs. The first two questions are OK, but to any experienced coder they are automatically considered part of fixing the bug and not afterthoughts. The third question, "What should I do to prevent bugs like this?", is especially important because once you learn to identify where and how bugs can occur you can markedly decrease their occurrence, which makes everyone involved happier.