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What is “:-!!” in C code?
...sizeof(struct { int: -!!(e); }))
(e): Compute expression e.
!!(e): Logically negate twice: 0 if e == 0; otherwise 1.
-!!(e): Numerically negate the expression from step 2: 0 if it was 0; otherwise -1.
struct{int: -!!(0);} --> struct{int: 0;}: If it was zero, then we declare a struct with an an...
Regular expression for letters, numbers and - _
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To actually cover your pattern, i.e, valid file names according to your rules, I think that you need a little more. Note this doesn't match legal file names from a system perspective. That would be system dependent and more libera...
How to use java.net.URLConnection to fire and handle HTTP requests?
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First a disclaimer beforehand: the posted code snippets are all basic examples. You'll need to handle trivial IOExceptions and RuntimeExceptions like NullPointerException, ArrayIndexOutOfBoundsException and consorts yourself.
Preparing
We first need to know at least the URL and the c...
How to use timeit module
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The way timeit works is to run setup code once and then make repeated calls to a series of statements. So, if you want to test sorting, some care is required so that one pass at an in-place sort doesn't affect the next pass with already sorted data (that, of course, would make the Timsort reall...
What is the difference between lock and Mutex?
...re are several other "minor" differences, like how abandonment is handled, etc.
The same can be said about ReaderWriterLock and ReaderWriterLockSlim in 3.5, Semaphore and the new SemaphoreSlim in .NET 4.0 etc.
It is true that the latter xxSlim classes cannot be used as a system-wide sync primitives...
Why shouldn't I use mysql_* functions in PHP?
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The MySQL extension:
Is not under active development
Is officially deprecated as of PHP 5.5 (released June 2013).
Has been removed entirely as of PHP 7.0 (released December 2015)
This means that as of 31 Dec 2018 it does not exist in any supported version of PHP. If you are using a ve...
How to declare string constants in JavaScript? [duplicate]
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There's no constants in JavaScript, but to declare a literal all you have to do is:
var myString = "Hello World";
I'm not sure what you mean by store them in a resource file; that's not a JavaScript concept.
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How do you do Impersonation in .NET?
...asy
WindowsIdentity.Impersonate Method (check out the code samples)
Basically you will be leveraging these classes that are out of the box in the .NET framework:
WindowsImpersonationContext
WindowsIdentity
The code can often get lengthy though and that is why you see many examples like the on...
Tree data structure in C#
...e so many ways you could implement it that it would be impossible to cover all bases with one solution. The more specific a solution, the less likely it is applicable to any given problem. I even get annoyed with LinkedList - what if I want a circular linked list?
The basic structure you'll need ...
Django - how to create a file and save it to a model's FileField?
...nt to have a look at FileField and FieldFile in the Django docs, and especially FieldFile.save().
Basically, a field declared as a FileField, when accessed, gives you an instance of class FieldFile, which gives you several methods to interact with the underlying file. So, what you need to do is:
s...