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What does the slash mean in help() output?
...python functions.
Also see the Argument Clinic documentation:
To mark all parameters as positional-only in Argument Clinic, add a / on a line by itself after the last parameter, indented the same as the parameter lines.
and the (very recent addition to) the Python FAQ:
A slash in the argu...
Is there a benefit to defining a class inside another class in Python?
What I'm talking about here are nested classes. Essentially, I have two classes that I'm modeling. A DownloadManager class and a DownloadThread class. The obvious OOP concept here is composition. However, composition doesn't necessarily mean nesting, right?
...
When are C++ macros beneficial? [closed]
...nned by the C++ community. In-lined functions, consts and templates are usually a safer and superior alternative to a #define .
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Python extending with - using super() Python 3 vs Python 2
Originally I wanted to ask this question , but then I found it was already thought of before...
5 Answers
...
What are “first class” objects?
...as
any other object.
A first class object is an entity that can be dynamically created, destroyed, passed to a function, returned as a value, and have all the rights as other variables in the programming language have.
Depending on the language, this can
imply:
being expressible as ...
sql “LIKE” equivalent in django query
...s. I have made the lookup into a Django-like-lookup application. After installing it the __like lookup with the % and _ wildcards will be enabled.
All the necessary code in the application is:
from django.db.models import Lookup
from django.db.models.fields import Field
@Field.register_lookup
cl...
Creating a singleton in Python
...mple implementation:
class Singleton(type):
_instances = {}
def __call__(cls, *args, **kwargs):
if cls not in cls._instances:
cls._instances[cls] = super(Singleton, cls).__call__(*args, **kwargs)
return cls._instances[cls]
class Logger(object):
__meta...
Is it intended by the C++ standards committee that in C++11 unordered_map destroys what it inserts?
... always move from its argument. It's supposed to move if the argument is really an rvalue, and copy if it's an lvalue.
The behaviour, you observe, which always moves, is a bug in libstdc++, which is now fixed according to a comment on the question. For those curious, I took a look at the g++-4.8 he...
Pandas - How to flatten a hierarchical index in columns
..., but leaves behind column names which are difficult to access programmatically and are not queriable
– dmeu
Jun 29 '17 at 8:53
1
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How to get the full path of running process?
...
According to my measurements, calling process.Modules[0] is 50 times slower than calling process.MainModule.
– Luca Cremonesi
Oct 23 '14 at 16:14
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