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Check if an apt-get package is installed and then install it if it's not on Linux
I'm working on a Ubuntu system and currently this is what I'm doing:
22 Answers
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Is Javascript a Functional Programming Language?
Just because functions are first class objects, there are closures, and higher order functions, does Javascript deserve to be called a Functional Programming language? The main thing I think it lacks is Pure Functions, and it doesn't 'feel' like other functional languages, like lisp (although thats...
Multiple working directories with Git?
...t for contrib/workdir/git-new-workdir that does not rely on symbolic links and make sharing of objects and refs safer by making the borrowee and borrowers aware of each other.
See commit 799767cc9 (Git 2.5rc2)
That means you now can do a git worktree add <path> [<branch>]
Create <pa...
What's a concise way to check that environment variables are set in a Unix shell script?
...(an empty string) is OK — not exactly what you want, but the alternative and older notation.
The second variant (using :?) requires DEST to be set and non-empty.
If you supply no message, the shell provides a default message.
The ${var?} construct is portable back to Version 7 UNIX and the Bourne ...
Splitting templated C++ classes into .hpp/.cpp files--is it possible?
...ors trying to compile a C++ template class which is split between a .hpp and .cpp file:
16 Answers
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ETag vs Header Expires
...d around but haven't been able to figure out if I should use both an ETag and an Expires Header or one or the other.
8 ...
How do I create a custom iOS view class and instantiate multiple copies of it (in IB)?
...mer in IB simply drag out a UIView drop it on your view controller's view, and set it's class to your timer's class name.
Remember to #import your timer class in your view controller.
Edit: for IB design (for code instantiation see revision history)
I'm not very familiar at all with storyboard,...
How do I get the type of a variable?
...ns integer on your compiler. The names returned are not specified by the standard.
– Bo Persson
Jul 3 '12 at 12:59
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Center a position:fixed element
...a position: fixed; popup box centered to the screen with a dynamic width and height. I used margin: 5% auto; for this. Without position: fixed; it centers fine horizontally, but not vertically. After adding position: fixed; , it's even not centering horizontally.
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System.Timers.Timer vs System.Threading.Timer
I have been checking out some of the possible timers lately, and System.Threading.Timer and System.Timers.Timer are the ones that look needful to me (since they support thread pooling).
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