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Cost of exception handlers in Python
...nt division or modulo by zero
So, as expected, not having any exception handler is slightly faster (but blows up in your face when the exception happens), and try/except is faster than an explicit if as long as the condition is not met.
But it's all within the same order of magnitude and unlikel...
How can I efficiently select a Standard Library container in C++11?
...art is slightly off, because list is not such a good container in general, and neither is forward_list. Both lists are very specialized containers for niche applications.
To build such a chart, you just need two simple guidelines:
Choose for semantics first
When several choices are available, go ...
How can I negate the return-value of a process?
...at negates the value a process returns. It should map 0 to some value != 0 and any value != 0 to 0, i.e. the following command should return "yes, nonexistingpath doesn't exist":
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How to permanently export a variable in Linux?
I am running RHEL6, and I have exported an environment variable like this:
6 Answers
6...
Is == in PHP a case-sensitive string comparison?
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== is case sensitive, some other operands from the php manual to familiarize yourself with
http://www.php.net/manual/en/language.operators.comparison.php
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How can I alter a primary key constraint using SQL syntax?
...rimary key constraint name, use query found here to look it up (or look up and drop all at once). http://stackoverflow.com/a/13948609/945875
– Justin
Dec 19 '13 at 20:06
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Compare integer in bash, unary operator expected
...at variable substitutions are done, the shell proceeds with the comparison and.... fails because it cannot see anything intelligible to the left of -gt. However, quoting $i:
if [ "$i" -ge 2 ] ; then ...
becomes:
if [ " " -ge 2 ] ; then ...
The shell now sees the double-quotes, and knows th...
Intel HAXM installation error - This computer does not support Intel Virtualization Technology (VT-x
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Just follows these steps:
Go to Control Panel → Program and Feature.
Click on Turn Window Features on and off. A window opens.
Uncheck Hyper-V and Windows Hypervisor Platform options and restart your system.
Now, you can Start HAXM installation without any error.
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Twig: in_array or similar possible within if statement?
I am using Twig as templating engine and I am really loving it. However, now I have run in a situation which definitely mustbe accomplishable in a simpler way than I have found.
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Custom attributes - Yea or nay?
Recently I have been reading more and more about people using custom attributes in their HTML tags, mainly for the purpose of embedding some extra bits of data for use in javascript code.
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