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What's a correct and good way to implement __hash__()?
What's a correct and good way to implement __hash__() ?
6 Answers
6
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Casting vs using the 'as' keyword in the CLR
...g, which has largely replaced the as operator, as you can now write:
if (randomObject is TargetType tt)
{
// Use tt here
}
Note that tt is still in scope after this, but not definitely assigned. (It is definitely assigned within the if body.) That's slightly annoying in some cases, so if you ...
Compile, Build or Archive problems with Xcode 4 (and dependencies)
...ed over the past several weeks to cover more general issues with xcode4 (and upgrading projects form older xcode s).
14 ...
Convert .pem to .crt and .key
Can anyone tell me the correct way/command to extract/convert the certificate .crt and private key .key files from a .pem file? I just read they are interchangable, but not how.
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What is the difference between range and xrange functions in Python 2.X?
Apparently xrange is faster but I have no idea why it's faster (and no proof besides the anecdotal so far that it is faster) or what besides that is different about
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When should we use Observer and Observable?
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You have a concrete example of a Student and a MessageBoard. The Student registers by adding itself to the list of Observers that want to be notified when a new Message is posted to the MessageBoard. When a Message is added to the MessageBoard, it iterates over it...
Why does ContentResolver.requestSync not trigger a sync?
...rn as discussed at Google IO - slide 26. My content provider is working, and my sync works when I trigger it from the Dev Tools Sync Tester application, however when I call ContentResolver.requestSync(account, authority, bundle) from my ContentProvider, my sync is never triggered.
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Can't update Macports (with Mac OS X Mavericks)
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Install the "Command Line Tools" first:
sudo xcode-select --install
(Explicitly agreeing to the license is sometimes necessary via "sudo xcodebuild -license")
Then upgrade the ports:
sudo port -v selfupdate
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What Every Programmer Should Know About Memory?
... fundamental concepts about memory: how CPU cache works, what are physical and virtual memory and how Linux kernel deals that zoo. Probably there are outdated API references in some examples, but it doesn't matter; that won't affect the relevance of the fundamental concepts.
So, any book or article...
CSS :after not adding content to certain elements
I'm having trouble understanding the behavior of the CSS :after property. According to the spec ( here and here ):
3 An...