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The term “Context” in programming? [closed]
I have been programming for some months now and a frequently used word is "context" in classes. Like ServletContext (Java), Activity (Android), Service (Java, Android), NSManagedContext (Objective-C, iOS).
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Bash conditionals: how to “and” expressions? (if [ ! -z $VAR && -e $VAR ])
I guess I'm not clear on how to do "and" tests. I wanted to make sure an argument existed which was working well with [ -e $VAR ] , but it turns out that was also evaluating as true on an empty string; which I do not want.
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How to do what head, tail, more, less, sed do in Powershell? [closed]
On windows, using Powershell, what are the equivalent commands to linux's head , tail , more , less and sed ?
7 Answe...
Hidden Features of C++? [closed]
... that it can be used as an lvalue:
(a == 0 ? a : b) = 1;
which is shorthand for
if (a == 0)
a = 1;
else
b = 1;
Use with caution :-)
share
edited Jan 7 '09 at 21:...
Find and Replace Inside a Text File from a Bash Command
What's the simplest way to do a find and replace for a given input string, say abc , and replace with another string, say XYZ in file /tmp/file.txt ?
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How to navigate back to the last cursor position in Visual Studio?
...ted Aug 11 '16 at 15:48
The One and Only ChemistryBlob
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answered May 7 '13 at 9:00
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javax vs java package
What's the rationale behind the javax package? What goes into java and what into javax?
7 Answers
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How can I repeat a character in Bash?
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You can use:
printf '=%.0s' {1..100}
How this works:
Bash expands {1..100} so the command becomes:
printf '=%.0s' 1 2 3 4 ... 100
I've set printf's format to =%.0s which means that it will always print a single = no matter what argument it is given. Therefore it prints 100 =s.
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Is System.nanoTime() completely useless?
...ventov's answer offers a more up-to-date perspective.
That post is wrong, and nanoTime is safe. There's a comment on the post which links to a blog post by David Holmes, a realtime and concurrency guy at Sun. It says:
System.nanoTime() is implemented using the QueryPerformanceCounter/QueryPerfo...
What is the difference between JOIN and UNION?
What is the difference between JOIN and UNION ? Can I have an example?
15 Answers
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