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Implementing slicing in __getitem__

... The __getitem__() method will receive a slice object when the object is sliced. Simply look at the start, stop, and step members of the slice object in order to get the components for the slice. >>> class C(object): ......
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Understanding slice notation

... It's pretty simple really: a[start:stop] # items start through stop-1 a[start:] # items start through the rest of the array a[:stop] # items from the beginning through stop-1 a[:] # a copy of the whole array There is also...
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How do I check in JavaScript if a value exists at a certain array index?

... Conceptually, arrays in JavaScript contain array.length elements, starting with array[0] up until array[array.length - 1]. An array element with index i is defined to be part of the array if i is between 0 and array.length - 1 inclu...
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ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/tmp/mysql.sock'

I installed MySQL on Mac OS X Mountain Lion with homebrew install mysql , but when I tried mysql -u root I got the following error: ...
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Is there a performance difference between i++ and ++i in C++?

... However, if i is an instance of a C++ class, then i++ and ++i are making calls to one of the operator++ functions. Here's a standard pair of these functions: Foo& Foo::operator++() // called for ++i { this->data += 1; return *this; } Foo Foo::operator++(int ignored_dummy_value) ...
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When to use EntityManager.find() vs EntityManager.getReference() with JPA

... I usually use getReference method when i do not need to access database state (I mean getter method). Just to change state (I mean setter method). As you should know, getReference returns a proxy object which uses a powerful featu...
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One-liner to check whether an iterator yields at least one element?

... Similarly if you need to check if the iterator is empty, one could use all(False for _ in iterator) will check if the iterator is empty. (all returns True if the iterator is empty, otherwise it stops when it sees the first False element) – KGardevoir Apr 3 ...
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How is __eq__ handled in Python and in what order?

... The a == b expression invokes A.__eq__, since it exists. Its code includes self.value == other. Since int's don't know how to compare themselves to B's, Python tries invoking B.__eq__ to see if it knows how to compare itself to an int. If you amend your ...
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Unit Testing AngularJS directive with templateUrl

... You're correct that it's related to ngMock. The ngMock module is automatically loaded for every Angular test, and it initializes the mock $httpBackend to handle any use of the $http service, which includes template fetching. The template system tries to load the template through $http and it become...
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Reliable method to get machine's MAC address in C#

...work across OS. Any ideas? I have been scraping the output of "ipconfig /all" but this is terribly unreliable as the output format differs on every machine. ...