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When should we use Observer and Observable?
...ause it separates the part where you say that the Observable has changed, from the part where you notify the changes. (E.g. Its useful if you have multiple changes happening and you only want to notify at the end of the process rather than at each small step). This is done through setChanged(). So ...
How to create NS_OPTIONS-style bitmask enumerations in Swift?
... 0 }
static var allZeros: MyOptions { return self(0) }
static func fromMask(raw: UInt) -> MyOptions { return self(raw) }
var rawValue: UInt { return self.value }
static var None: MyOptions { return self(0) }
static var FirstOption: MyOptions { return self(1 << 0) }
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What is the purpose of `text=auto` in `.gitattributes` file?
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From the docs:
Each line in .gitattributes (or .git/info/attributes) file is of form:
pattern attr1 attr2 ...
So here, the pattern is *, which means all files, and the attribute is text=auto.
What does text=auto do?...
difference between each.with_index and each_with_index in Ruby?
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to allow wider usage with various enumerators.
to allow index to start from a number other than 0.
Today, using with_index would be better from the point of view of generality and readability, but from the point of view of speeding up the code, each_with_index runs slightly faster than each.wi...
Why does X[Y] join of data.tables not allow a full outer join, or a left join?
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To quote from the data.table FAQ 1.11 What is the difference between X[Y] and merge(X, Y)?
X[Y] is a join, looking up X's rows using Y (or Y's key if it has one) as an index.
Y[X] is a join, looking up Y's rows using X (or X'...
Why isn't `int pow(int base, int exponent)` in the standard C++ libraries?
...s based, also had no use for powers (it didn't have floating point at all, from memory).
As an aside, an integral power operator would probably have been a binary operator rather than a library call. You don't add two integers with x = add (y, z) but with x = y + z - part of the language proper ...
How to retrieve the first word of the output of a command in bash?
...or example: echo "word1 word2" . I want to put a pipe ( | ) and get word1 from the command.
12 Answers
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How do I represent a time only value in .NET?
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@sduplooy: Fancy helping us port it from Joda Time then? :)
– Jon Skeet
Jan 10 '10 at 15:23
1
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How do I write a bash script to restart a process if it dies?
... restarting and crashing on your hands. The sleep 1 takes away the strain from that.
Now all you need to do is start this bash script (asynchronously, probably), and it will monitor myserver and restart it as necessary. If you want to start the monitor on boot (making the server "survive" reboots...
Scatterplot with marginal histograms in ggplot2
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You're right. They're sampled from the same distribution though, so the marginal histograms should theoretically match the scatter plot.
– oeo4b
Dec 17 '11 at 17:03
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