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When should I use nil and NULL in Objective-C?
... technically, they are exactly equal, you can send messages to both nil and to NULL. Idiomatically though nil is usually used to represent an object
– cobbal
Oct 14 '09 at 5:43
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NPM cannot install dependencies - Attempt to unlock something which hasn't been locked
...per photusenigma at: https://github.com/npm/npm/issues/4815
Run these commands in a terminal window (note - DON'T replace the $USER part...thats a linux command to get your user!):
sudo chown -R $USER ~/.npm
sudo chown -R $USER /usr/local/lib/node_modules
...and...if you're on a mac (like I am),...
C++ Const Usage Explanation
...hanged, to an int that cannot be changed: the only difference between this and const int& is that it can be null
const int* const& means a reference to a constant pointer to a constant int. Usually pointers are not passed by reference; const int* & makes more sense because it would mean...
How can I add a custom HTTP header to ajax request with js or jQuery?
...e of is that with ajaxSetup you can only define one set of default headers and you can only define one beforeSend. If you call ajaxSetup multiple times, only the last set of headers will be sent and only the last before-send callback will execute.
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rmagick gem install “Can't find Magick-config”
...stall the rmagick gem. I am on Snowleopard 10.6 using RVM, Ruby 1.9.2-head and Rails 3.05. Responses to similar questions recommended installing ImageMagick, which I successfully did. Other suggested installing the "libmagick9-dev library", however, I can not figure out how to do this.
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What guarantees are there on the run-time complexity (Big-O) of LINQ methods?
I've recently started using LINQ quite a bit, and I haven't really seen any mention of run-time complexity for any of the LINQ methods. Obviously, there are many factors at play here, so let's restrict the discussion to the plain IEnumerable LINQ-to-Objects provider. Further, let's assume that any...
Object reference not set to an instance of an object.Why doesn't .NET show which object is `null`?
Regarding this .NET unhandled exception message:
5 Answers
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What is the difference between self-types and trait subclasses?
...njection in Scala, including the Cake Pattern. If you Google "Cake Pattern and Scala", you'll get many links, including presentations and videos. For now, here is a link to another question.
Now, as to what is the difference between a self type and extending a trait, that is simple. If you say B ex...
Catching an exception while using a Python 'with' statement
To my shame, I can't figure out how to handle exception for python 'with' statement. If I have a code:
4 Answers
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“Origin null is not allowed by Access-Control-Allow-Origin” error for request made by application ru
I'm developing a page that pulls images from Flickr and Panoramio via jQuery's AJAX support.
17 Answers
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