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How do I get the object if it exists, or None if it does not exist?
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Why does sun.misc.Unsafe exist, and how can it be used in the real world?
...NI calls into native code that contains special instructions for CAS
read more about CAS here http://en.wikipedia.org/wiki/Compare-and-swap
The sun.misc.Unsafe functionality of the host VM can be used to allocate uninitialized objects and then interpret the constructor invocation as any other metho...
How to give Jenkins more heap space when it´s started as a service under Windows?
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What is the most pythonic way to check if an object is a number?
... '2' False
This is, of course, contrary to duck typing. If you are more concerned about how an object acts rather than what it is, perform your operations as if you have a number and use exceptions to tell you otherwise.
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Remove local git tags that are no longer on the remote repository
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Richard W's answer does this much more elegantly, in case you are not interested in a complicated script.
– Kyle Heironimus
Feb 11 '13 at 19:28
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Check existence of input argument in a Bash shell script
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Escape a string for a sed replace pattern
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Warning: This does not consider newlines. For a more in-depth answer, see this SO-question instead. (Thanks, Ed Morton & Niklas Peter)
Note that escaping everything is a bad idea. Sed needs many characters to be escaped to get their special meaning. For example, if yo...
What is a NullReferenceException, and how do I fix it?
... or shorter if (a != null) { b = a; }.
The rest of this article goes into more detail and shows mistakes that many programmers often make which can lead to a NullReferenceException.
More Specifically
The runtime throwing a NullReferenceException always means the same thing: you are trying to use a ...
Best way to simulate “group by” from bash?
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one more tweak for sort part: sort -nr -k1,1
– Andrzej Martyna
Dec 10 '19 at 10:19
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Recursive Lock (Mutex) vs Non-Recursive Lock (Mutex)
...d originally took the mutex. In many cases, this type of "mutex" is really more of a semaphore action, where you are not necessarily using the mutex as an exclusion device but use it as synchronization or signaling device between two or more threads.
Another property that comes with a sense of owne...