Hoare logic, despite its mathematical sounding name, is actually a quite practical way of reasoning about programs that most software engineers subconsciously employ in the form of preconditions and postconditions. It explicitly axiomatizes things that are common sense to a programmer: for example, a NOP should not change any conditions, or if a line of code has a postcondition that another line of code has as its precondition, those lines of code can be executed one after another and the inner precondition-postcondition pair ignored. Even if you never actually write out the derivation chains, you’re informally applying Hoare logic when you are trying to review code that uses preconditions and postconditions. Hoare logic is an abstraction that lets us rigorously talk about any imperative language with the same set of rules.
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I am studying computer science this academic year at Cambridge University, not MIT. For some people, this seems quite strange: when I tell old friends at MIT and new acquaintances at Cambridge about the fact that I am a Cambridge-MIT Exchange student, they say, “Why?” Sometimes, it’s some disbelief at the fact that I am choosing to leave the familiar social circles and situations that mark MIT. Other times, it’s some disbelief that I would want to study computer science at Cambridge rather than MIT (“Just joking,” they add, though I’m not necessarily sure I believe them.)
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A hackathon is an event, spanning from a day to a week, where hackers (not the cracking kind) get together to work on some common goals in concert. One use of a hackathon is to get some open-source contributors together and work hard on a particular feature: the combination of being together and being expected to work on the task at hand means that people are more productive than they would be if they were just working alone.
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