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How to determine if a number is a prime with regex?
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You said you understand this part, but just to emphasize, the String generated has a length equal to the number supplied. So the string has three characters if and only if n == 3.
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The first part of the regex says, "any character, zero or one times". So basically, is there ...
Proper practice for subclassing UIView?
...ve the awakeFromNib opportunity to perform custom frame and layout initializations, since when awakeFromNib is called it's guaranteed that every view in the hierarchy has been unarchived and initialized.
From the doc of NSNibAwaking (now superseded by the doc of awakeFromNib):
Messages to other...
What is the difference between class and instance attributes?
...entry
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How does lucene index documents?
... think of it as a bit like a hashtable.
Terms are generated using an analyzer which stems each word to its root form. The most popular stemming algorithm for the english language is the Porter stemming algorithm: http://tartarus.org/~martin/PorterStemmer/
When a query is issued it is processed thr...
In HTML5, should the main navigation be inside or outside the element?
...evlin
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How to create an object for a Django model with a many to many field?
...olmes
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answered Aug 9 '11 at 12:43
Daniel HepperDaniel Hepper
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What does the thread_local mean in C++11?
...bal/static variables can be accessed by all the threads (possibly synchronized access using locks). And the thread_local variables are visible to all the threads but can only modified by the thread for which they are defined? Is it correct?
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What does .SD stand for in data.table in R
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answered Dec 14 '11 at 17:53
Josh O'BrienJosh O'Brien
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Strange, unexpected behavior (disappearing/changing values) when using Hash default value, e.g. Hash
...s immutable, we could use Hash.new([]) just fine too:
h = Hash.new([].freeze)
h[0] += ['a'] #=> ["a"]
h[1] += ['b'] #=> ["b"]
h[2] #=> []
h #=> {0=>["a"], 1=>["b"]}
However, note that ([].freeze + [].freeze).frozen? == false. So, if you want to ensure th...
Why and How to avoid Event Handler memory leaks?
I just came to realize, by reading some questions and answers on StackOverflow, that adding event handlers using += in C# (or i guess, other .net languages) can cause common memory leaks...
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