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Comment by jimmaswell | Hacker News Reader

I don't look at my libraries' source unless I have a problem the documentation or google doesn't answer. that's really going to be your fizzbuzz?

A lot of the time I don't need the docs anyway, I just find what I'm looking for in the iltellisense/other suggestions because the OO model makes this work great.

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  unless I have a problem the documentation or google doesn't answer

Documentation/googling is definitely the right thing to do off the bat. But if they've never had a moment where they had to peek under the hood (or never thought to try, or didn't know how to) then yes, that's my FizzBuzz. I would perhaps not apply this to someone fresh out of school, but I would expect an experienced candidate to know how to "use the source".

There is a difference between knowing how to do something and thinking it's a good idea.

Obviously if you need to look at your code for pragmatic purposes, that's fine; but if reading third-party code becomes your modus operandi, you just might be using crappy libraries.

I'm using Spring 3.1, Jetty, various OWASP, guava. I am in the code of Spring and Jetty on a daily basis, and OWASP when I first used it. I learned guava by writing unit tests to verify my assumptions - assumptions I learned from the documentation - and which turned out to be mostly wrong.

Documentation is ambiguous, and even document which is unambiguous is often wrong.

Writing unit tests is a nice way to work when you're not working in an environment that requires young goat sacrifices or some such thing to perform unit tests. I'd also say that some kinds of unit tests are also a limited form of documentation. They don't tell you why something works the way it does, but they do tell you how it works.

> you just might be using crappy libraries.

Maybe, but sometimes you're stuck with crappy libraries or even crappy frameworks. The last time I had to really dig deep into (ie spend more than 30 mins reading) 3rd party code was when I was trying to figure out if a method in Android's WebView was synchronous or not. [0] Maybe the Android framework, or the WebView specifically is a "crappy library" (the documentation in this case was definitely crappy) but "not using WebView" or "not using Android" wasn't an option.

[0] http://stackoverflow.com/questions/10962150/understanding-an...

Yes, this is certainly a reality for a lot of programmers.

> you just might be using crappy libraries

Also, writing crappy code. If you are relying on undocumented behavior, it might well change under you. Looking past the abstraction is sometimes necessary, but it should be the exception.

I actually looked at the sfml source once to find out why vector*.x/y wasn't returning an lvalue in .net. Only time I can think of though.

turned out it was an issue woth out it used Properties.

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