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Comment by noelwelsh | Hacker News Reader

In my mind condition variables are stored under "crap I don't need to know because we have better abstractions". I can understand why RethinkDB will be messing around with semaphores (or monitors aka condition variables) but for most programs there are far better ways to organise concurrency. Java recognises this -- experience showed the synchronized (monitor) approach to concurrency to be too unwieldy and it was superseded fairly quickly by java.util.concurrent and friends. Way back in 2000 we were using Doug Lea's concurrency library, which formed the basis for java.util.concurrent. I certainly could use semaphores but it would certainly take me some time to adjust my thinking to that primitive model.

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That's an applications-programmer answer. But who did you think wrote java.util.concurrent? The article is by someone who needs systems programmers, who do algorithmic work, not applications programmers, who put together large state-diagram code.

Doug Lea is my guess. We were writing algorithms, but they were machine learning algorithms so implementing our own concurrency abstractions wasn't a win.

Hah, I suspected as much from the article's title.

Systems Programmers = "real" programmers (for the article's writers)

Application Programmers (or even worse, Information Systems guys like myself) are not "real" programmers to them - and to be honest, I don't believe myself a "real" programmer sometimes as well.

This is exactly the kind of answer we're looking for.

Yes, yes indeed. Looking at it like that, it is great a response, but there's still a problem...

Given the rather adversarial nature of the technical interview setting, there's pretty much zero probability you'd actually get that answer from him.

This presents an interesting dilemma.

> the rather adversarial nature of the technical interview setting

Interviews are a way for two parties to determine if it would be mutually beneficial for them to have a long-term relationship. They are no more adversarial than flirting or dating are.

If someone is capable of expressing this somewhat adversarial opinion in an interview, then they are also capable of expressing valuable opinions in "real life" that might go against the status quo. This could be a very good thing.

It's also a great filter when you are the job seeker. If they want a yes man, they won't hire you.

Had no idea what Condition Variables were. Honestly. However after reading up on them I realized I've been using them for a looooong time, they just seemed so natural a solution to a problem. Most simple patterns can be derived by yourself without any help because they really fit the solution so well that it feels unnatural to not think of them. Some of the more interesting ones are removing complexities :)

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