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How to swap two variables in JavaScript
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Here's a one-liner to swap the values of two variables.
Given variables a and b:
b = [a, a = b][0];
Demonstration below:
var a=1,
b=2,
output=document.getElementById('output');
output.innerHTML="<p>Original: "+a+", "+b+"</p>";
b = [a, a = b][0];
output.innerHT...
How to use subprocess popen Python
...ata. A clever attacker can modify the input to access arbitrary system commands. E.g. by inputting filename.swf; rm -rf / for the value of filename. However, this is only a problem, when the contents of your argument to Popen is insecure.
– Hans Then
Sep 26 '12...
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
22
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Rotated elements in CSS that affect their parent's height correctly
...kes undefined behaviour according to the CSS 2 spec - so while I've tested and confirmed that it works in Chrome, Firefox, Safari, and Edge, I can't promise you that it won't break in a future browser release.
Short answer
Given HTML like this, where you want to rotate .element-to-rotate...
<d...
Data structure for loaded dice?
...e. for a fixed set of probabilities) so that I can efficiently simulate a random roll of the die.
4 Answers
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Where does Jenkins store configuration files for the jobs it runs?
...itself is kept on an EC2 machine - one that might need to be taken offline and brought back on an entirely different EC2 instance at any point. We have a bunch of Puppet manifests allowing us to easily reinstall the software on the EC2 instance, but custom configuration files, like the ones for the ...
what is difference between success and .done() method of $.ajax
Can anyone help me?
I am not able to understand the difference between success and .done() of $.ajax .
4 Answers
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What's the best way to get the last element of an array without deleting it?
... many different options. To be able to choose from them I needed to understand their behavior and performance. In this answer I will share my findings with you, benchmarked against PHP versions 5.6.38, 7.2.10 and 7.3.0RC1 (expected Dec 13 2018).
The options (<<option code>>s) I will tes...
Is there a generator version of `string.split()` in Python?
...offset parameter of the str.find() method. This avoids lots of memory use, and relying on the overhead of a regexp when it's not needed.
[edit 2016-8-2: updated this to optionally support regex separators]
def isplit(source, sep=None, regex=False):
"""
generator version of str.split()
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Objective-C: Reading a file line by line
...e text files in Objective-C? Let's say I need to read each line separately and want to treat each line as an NSString. What is the most efficient way of doing this?
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