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What are inline namespaces for?
C++11 allows inline namespace s, all members of which are also automatically in the enclosing namespace . I cannot think of any useful application of this -- can somebody please give a brief, succinct example of a situation where an inline namespace is needed and where it is the most idiomatic s...
Python dictionary from an object's fields
...a dictionary from an arbitrary object, it's sufficient to use __dict__. Usually, you'll declare your methods at class level and your attributes at instance level, so __dict__ should be fine. For example:
>>> class A(object):
... def __init__(self):
... self.b = 1
... self.c = 2
....
How to create module-wide variables in Python? [duplicate]
...
Here is what is going on.
First, the only global variables Python really has are module-scoped variables. You cannot make a variable that is truly global; all you can do is make a variable in a particular scope. (If you make a variable inside the Python interpreter, and then import other mo...
How do I list all files of a directory?
How can I list all files of a directory in Python and add them to a list ?
21 Answers
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MySQL vs MongoDB 1000 reads
...very excited about MongoDb and have been testing it lately. I had a table called posts in MySQL with about 20 million records indexed only on a field called 'id'.
...
Can a decorator of an instance method access the class?
I have something roughly like the following. Basically I need to access the class of an instance method from a decorator used upon the instance method in its definition.
...
What does multicore assembly language look like?
...on, but it's an answer to a question that appears in the comments. Essentially, the question is what support the hardware gives to multi-threaded operation.
Nicholas Flynt had it right, at least regarding x86. In a multi threaded environment (Hyper-threading, multi-core or multi-processor), the B...
How do exceptions work (behind the scenes) in c++
...
Instead of guessing, I decided to actually look at the generated code with a small piece of C++ code and a somewhat old Linux install.
class MyException
{
public:
MyException() { }
~MyException() { }
};
void my_throwing_function(bool throwit)
{
if (...
Underscore vs Double underscore with variables and methods [duplicate]
...
Explanation:
People coming from a C++/Java background are especially prone to
overusing/misusing this "feature". But __private names don't work the
same way as in Java or C++. They just trigger a name mangling whose
purpose is to prevent accidental namespace collisions in subclasses...
Accessing dict keys like an attribute?
...__init__(*args, **kwargs)
self.__dict__ = self
Some pros:
It actually works!
No dictionary class methods are shadowed (e.g. .keys() work just fine. Unless - of course - you assign some value to them, see below)
Attributes and items are always in sync
Trying to access non-existent key as an...