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Why do we need boxing and unboxing in C#?
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Why
To have a unified type system and allow value types to have a completely different representation of their underlying data from the way that reference types represent their underlying data (e.g., an int is just a bucket of thirty-two bits which is completely ...
How does Java Garbage Collection work with Circular References?
... method that prints out a unique id for the object. You'll be able to see all the objects that reference each other get collected.
– Bill the Lizard
Dec 15 '09 at 20:45
4
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Recursive Lock (Mutex) vs Non-Recursive Lock (Mutex)
POSIX allows mutexes to be recursive. That means the same thread can lock the same mutex twice and won't deadlock. Of course it also needs to unlock it twice, otherwise no other thread can obtain the mutex. Not all systems supporting pthreads also support recursive mutexes, but if they want to be P...
Difference between an API and SDK
...ring in your house.
an SDK is implementation tooling. It's like a kit that allows** you to build something custom to hook up to the telephone system or electrical wiring.
*Anything can use an API. Some APIs have security provisions to require license keys, authentication, etc. which may prohibit c...
How to prevent favicon.ico requests?
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I will first say that having a favicon in a Web page is a good thing (normally).
However it is not always desired and sometime developers need a way to avoid the extra payload. For example an IFRAME would request a favicon without showing it.
Worst yet, in Chrome and Android an IFRAME will generate...
What is the difference between HashSet and List?
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Actually, I prefer the answer that points out that HashSets are suitable in cases that you can treat your collection as "bag items". Set operations are not so frequent as Containment checks. At any point that you have a set of un...
Curious null-coalescing operator custom implicit conversion behaviour
...l; there's no need to check it for null a second time just because we are calling a lifted conversion operator". We'd them optimize it away to just
new int?(op_Implicit(temp2.Value))
My guess is that we are somewhere caching the fact that the optimized form of (int?)Foo() is new int?(op_implici...
Why is NaN not equal to NaN? [duplicate]
...n this question pops up in searches.
NaN is designed to propagate through all calculations, infecting them like a virus, so if somewhere in your deep, complex calculations you hit upon a NaN, you don't bubble out a seemingly sensible answer. Otherwise by identity NaN/NaN should equal 1, along with ...
Issue pushing new code in Github
...s were rejected because the remote contains work that you do
not have locally.
You may want to find to follow this advice:
You may want to first merge the remote changes (e.g.,
'git pull') before pushing again.
That is:
git pull
# Fix any merge conflicts, if you have a `README.md` local...
How to duplicate a git repository? (without forking)
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@Thomas I just did this and yes, it preserved all of my history in the copy. Note that after you push and cd into the new repo, there's still nothing there because you've pushed to the remote, so you need to do a pull
– PfunnyGuy
Oc...