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Why is there a difference in checking null against a value in VB.NET and C#?
...ence gives NULL the semantics "I don't know yet". Then the comparison of 5 to "I don't know yet". is naturally "I don't know yet"; ie NULL. This has the additional advantage of mirroring the behaviour of NULL in (most if not all) SQL databases. This is also a more standard (than C#'s) interpretation...
How to generate a random string in Ruby
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(0...8).map { (65 + rand(26)).chr }.join
I spend too much time golfing.
(0...50).map { ('a'..'z').to_a[rand(26)] }.join
And a last one that's even more confusing, but more flexible and wastes fewer cycles:
o = [('a'..'z'), ('A'..'Z')].map(&:to_a).flatten
string = (0...
Copy folder recursively, excluding some folders
I am trying to write a simple bash script that will copy the entire contents of a folder including hidden files and folders into another folder, but I want to exclude certain specific folders. How could I achieve this?
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What's the difference between unit tests and integration tests? [duplicate]
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A unit test is a test written by the programmer to verify that a relatively small piece of code is doing what it is intended to do. They are narrow in scope, they should be easy to write and execute, and their effectiveness depends on what the programmer considers to be us...
Installing a local module using npm?
I have a downloaded module repo, I want to install it locally, not globally in another directory?
7 Answers
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The best way to remove duplicate values from NSMutableArray in Objective-C?
The best way to remove duplicate values ( NSString ) from NSMutableArray in Objective-C?
14 Answers
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How to deal with a slow SecureRandom generator?
If you want a cryptographically strong random numbers in Java, you use SecureRandom . Unfortunately, SecureRandom can be very slow. If it uses /dev/random on Linux, it can block waiting for sufficient entropy to build up. How do you avoid the performance penalty?
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Executors.newCachedThreadPool() versus Executors.newFixedThreadPool()
...in the queue until a thread is
available. If any thread terminates
due to a failure during execution
prior to shutdown, a new one will take
its place if needed to execute
subsequent tasks. The threads in the
pool will exist until it is explicitly
shutdown.
newCachedThreadPool
Cr...
What's Mongoose error Cast to ObjectId failed for value XXX at path “_id”?
When sending a request to /customers/41224d776a326fb40f000001 and a document with _id 41224d776a326fb40f000001 does not exist, doc is null and I'm returning a 404 :
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How to implement a good __hash__ function in python [duplicate]
When implementing a class with multiple properties (like in the toy example below), what is the best way to handle hashing?
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