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How to use base class's constructors and assignment operator in C++?
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You can explicitly call constructors and assignment operators:
class Base {
//...
public:
Base(const Base&) { /*...*/ }
Base& operator=(const Base&) { /*...*/ }
};
class Derived : public Base
{
int additional_;
public:
...
Checking for empty queryset in Django
...if not my_objects: to demonstrate that this is how they do it in the docs. All else is utterly irrelevant so I do not get your point. They could as well make a thousand queries and it would still be totally irrelevant as this is not the point of this answer, with which I make clear that I agree.
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Can PostgreSQL index array columns?
... to this question in the documentation. If a column is an array type, will all the entered values be individually indexed?
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TypeError: 'NoneType' object is not iterable in Python
... Correct, But the common scenario author intended here is totally to skip the for loop instead of raising an exception. Python's design is flawed here. When None is treated as an iterable it must return empty list at least. This exception never helped anyone in real life other than m...
Delete files older than 15 days using PowerShell
...is in the title of this post), but here's some code that will first delete all of the files older than 15 days, and then recursively delete any empty directories that may have been left behind. My code also uses the -Force option to delete hidden and read-only files as well. Also, I chose to not use...
Keyboard Interrupts with python's multiprocessing Pool
...s to set up the worker processes to ignore SIGINT altogether, and confine all the cleanup code to the parent process. This fixes the problem for both idle and busy worker processes, and requires no error handling code in your child processes.
import signal
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def init_worker():
signal.sign...
Git Bash is extremely slow on Windows 7 x64
...ve been using Git on both Windows and Ubuntu during the development of a small project, frequently flipping back and forth between the two. The issue is that Git Bash consistently becomes slow.
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How do Python's any and all functions work?
I'm trying to understand how the any() and all() Python built-in functions work.
8 Answers
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Python, remove all non-alphabet chars from string
... Hmm, I can quite track it down, but what about the pattern to remove all non-alphanumerics excluding spaces?
– KDecker
Mar 20 '14 at 0:45
1
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Mongoose: Get full list of users
I have tried to use Mongoose to send the list of all users as follows:
8 Answers
8
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