This type of mistake is so common that the programming community has a name for it: an OBOE, or an off-by-one error. Named after the symptom and not the cause, most off-by-one errors come from the complications of convincing code to run for a set number of times or count a certain number of things. I’m obsessed with one specific species of off-by-one error: the fence-post problem. Which is the second weapon in TheJosh’s arsenal. This mistake is called the fence-post problem because it is quintessentially described using the metaphor of a fence: if a fifty-meter stretch of fence has a post
...more
