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Java 8 NullPointerException in Collectors.toMap
The Java 8 Collectors.toMap throws a NullPointerException if one of the values is 'null'. I don't understand this behaviour, maps can contain null pointers as value without any problems. Is there a good reason why values cannot be null for Collectors.toMap ?
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Where does R store packages?
... I've got a dozen R manuals on my Kindle (including the 3,000+ page one) and wasn't aware of the Startup help file. I've been reading the manuals and hit a dead-end. Go figure it was a simple answer all along. Do I lose points for RTFM questions <- I don't have many to lose. Thanks again...
Perform commands over ssh with Python
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@Gabriel: one of the recent releases should have improved support on Windows. If it's still not working, please feel free to open an issue.
– Michael Williamson
Aug 25 '14 at 14:02
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How to parse JSON using Node.js? [closed]
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Anyone know why that's not in the official documentation? Or, if it is, where to find it?
– snapfractalpop
Mar 21 '12 at 18:58
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Meaning of “[: too many arguments” error from if [] (square brackets)
I couldn't find any one simple straightforward resource spelling out the meaning of and fix for the following BASH shell error, so I'm posting what I found after researching it.
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git rebase: “error: cannot stat 'file': Permission denied”
I'm using git, and made a small commit followed by a large one. I decided to use git rebase to squash the two commits together before pushing them. (I've never done this before.)
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Creating a div element in jQuery [duplicate]
...dTo('#parent');
Alternatively, you can use the .html() or .add() as mentioned in a different answer.
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Using -performSelector: vs. just calling the method
...ackground:withObject: and performSelectorOnMainThread:withObject:waitUntilDone: are often more useful. For spawning a background thread, and for calling back results to the main thread from said background thread.
– PeyloW
Sep 30 '09 at 8:36
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What does new self(); mean in PHP?
... the class that is used (we used MyChildClass::getInstance()), and not the one in which it is written.
Of course, the behavior of self has not been changed, to not break existing applications -- PHP 5.3 just added a new behavior, recycling the static keyword.
And, speaking about PHP 5.3, you migh...
Value cannot be null. Parameter name: source
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I had this one a while back, and the answer isn't necessarily what you'd expect. This error message often crops up when your connection string is wrong.
At a guess, you'll need something like this:
<connectionStrings>
<ad...