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Why can't I use a list as a dict key in python?
..., with the hash as, say, their memory location?
It can be done without really breaking any of the requirements, but it leads to unexpected behavior. Lists are generally treated as if their value was derived from their content's values, for instance when checking (in-)equality. Many would - underst...
Why do we need virtual functions in C++?
... a rat."
So far so good, right? Animals eat generic food, cats eat rats, all without virtual.
Let's change it a little now so that eat() is called via an intermediate function (a trivial function just for this example):
// This can go at the top of the main.cpp file
void func(Animal *xyz) { xyz-...
What are rvalues, lvalues, xvalues, glvalues, and prvalues?
...e they needed? Probably not if we wish to forfeit the new features. But to allow better optimization we should probably embrace them.
Quoting n3055:
An lvalue (so-called, historically,
because lvalues could appear on the
left-hand side of an assignment
expression) designates a function or
an obj...
PHP Session Security
...or maintaining responsible session security with PHP? There's information all over the web and it's about time it all landed in one place!
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Determine the type of an object?
...object, and isinstance() to check an object’s type against something. Usually, you want to use isistance() most of the times since it is very robust and also supports type inheritance.
To get the actual type of an object, you use the built-in type() function. Passing an object as the only param...
Javascript/DOM: How to remove all events of a DOM object?
Just question: Is there any way to completely remove all events of an object, e.g. a div?
12 Answers
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What does 'super' do in Python?
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What's the difference?
SomeBaseClass.__init__(self)
means to call SomeBaseClass's __init__. while
super(Child, self).__init__()
means to call a bound __init__ from the parent class that follows Child in the instance's Method Resolution Order (MRO).
If the instance is a subclass of ...
Get model's fields in Django
Given a Django model, I'm trying to list all of its fields. I've seen some examples of doing this using the _meta model attribute, but doesn't the underscore in front of meta indicate that the _meta attribute is a private attribute and shouldn't be accessed directly? ... Because, for example, the ...
Scala: List[Future] to Future[List] disregarding failed futures
...ures to a Future of List. I'm using Playframework, so ultimately, what I really want is a Future[Result] , but to make things simpler, let's just say Future[List[Int]] The normal way to do this would be to use Future.sequence(...) but there's a twist... The list I'm given usually has around 10-...
Getters \ setters for dummies
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Isnt it really painful that MS does not support JS correctly and they do not make their silverlight run everywhere, so I have to program everything twice, one for SL and one for rest of the world :)
– Akash Kava
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