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Difference between static class and singleton pattern?
What real (i.e. practical) difference exists between a static class and a singleton pattern?
39 Answers
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“x not in y” or “not x in y”
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They always give the same result.
In fact, not 'ham' in 'spam and eggs' appears to be special cased to perform a single "not in" operation, rather than an "in" operation and then negating the result:
>>> import dis
>>> def notin():
'ham' not in 'spam and eggs'
&g...
PATH issue with pytest 'ImportError: No module named YadaYadaYada'
I used easy_install to install pytest on a mac and started writing tests for a project with a file structure likes so:
20 A...
How do I determine the dependencies of a .NET application?
...oes Dependency Walker work with managed apps? I've downloaded the latest and tried profiling the app, but it just exits without much of an explanation. If it doesn't work with .NET, then is there some other tool that would help me debug a run-time DLL loading issue?
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What are the aspect ratios for all Android phone and tablet devices?
I'm looking for a list of all screen aspect ratios for popular Android based Phones and Tablets.
5 Answers
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Spark java.lang.OutOfMemoryError: Java heap space
... suggestions:
If your nodes are configured to have 6g maximum for Spark (and are leaving a little for other processes), then use 6g rather than 4g, spark.executor.memory=6g. Make sure you're using as much memory as possible by checking the UI (it will say how much mem you're using)
Try using more ...
Is it possible to set the stacking order of pseudo-elements below their parent element? [duplicate]
...ange the default stacking order.
Positioning the pseudo-element (absolute) and assigning a z-index value other than “auto” creates the new stacking context.
#element {
position: relative; /* optional */
width: 100px;
height: 100px;
background-color: blue;
}
#elemen...
What's the difference between lapply and do.call?
I'm learning R recently and confused by two function: lapply and do.call . It seems that they're just similar to map function in Lisp. But why are there two functions with such a different name? Why doesn't R just use a function called map ?
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When to dispose CancellationTokenSource?
...ll Dispose on CancellationTokenSource... I had a memory leak in my project and it turned out that CancellationTokenSource was the problem.
My project has a service, that is constantly reading database and fires off different tasks, and I was passing linked cancellation tokens to my workers, so even...
Dynamic variable names in Bash
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Use an associative array, with command names as keys.
# Requires bash 4, though
declare -A magic_variable=()
function grep_search() {
magic_variable[$1]=$( ls | tail -1 )
echo ${magic_variable[$1]}
}
If you can't use associative arrays (e.g., you m...