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How can I use pointers in Java?
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All objects in Java are references and you can use them like pointers.
abstract class Animal
{...
}
class Lion extends Animal
{...
}
class Tiger extends Animal
{
public Tiger() {...}
public void growl(){...}
}
Tiger fi...
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 ...
How do I check in JavaScript if a value exists at a certain array index?
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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...
How is __eq__ handled in Python and in what order?
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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 ...
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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Unit Testing AngularJS directive with templateUrl
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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...
Is there a performance difference between i++ and ++i in C++?
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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) ...
When to use EntityManager.find() vs EntityManager.getReference() with JPA
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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...
Why can I not push_back a unique_ptr into a vector?
...to a local variable. The lifetime of a local variable is managed automatically: local variables are destroyed when the block ends (e.g., when the function returns, in this case). You need to dynamically allocate the object:
std::unique_ptr<int> ptr(new int(1));
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MVVM in WPF - How to alert ViewModel of changes in Model… or should I?
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RaisePropertyChanged("ViewModelCopyOfSomeProperty");
}
But typically this is only needed if more than one object will be making changes to the Model's data, which is not usually the case.
If you ever have a case where you don't actually have a reference to your Model property to attach t...