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Behaviour of increment and decrement operators in Python
...e applied on a variable (like ++count ). It compiles, but it does not actually change the value of the variable!
9 Answers...
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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Python executable not finding libpython shared library
I am installing Python 2.7 on CentOS 5. I built and installed Python as follows
9 Answers
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mongodb group values by multiple fields
... $slice just off the basic aggregation result. For "large" results, run parallel queries instead for each grouping ( a demonstration listing is at the end of the answer ), or wait for SERVER-9377 to resolve, which would allow a "limit" to the number of items to $push to an array.
db.books.aggregate(...
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 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:
...
Why is it impossible to override a getter-only property and add a setter? [closed]
Why is the following C# code not allowed:
16 Answers
16
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How to remove from a map while iterating it?
...= m.erase(it)" since C++11
}
else
{
++it;
}
}
Note that we really want an ordinary for loop here, since we are modifying the container itself. The range-based loop should be strictly reserved for situations where we only care about the elements. The syntax for the RBFL makes this clear...
MongoDB mongorestore failure: locale::facet::_S_create_c_locale name not valid
...
On my distro "locale-gen" was not installed and it turned out all I had to do is set the LC_ALL environment variable.
so the following command fixed it:
export LC_ALL="en_US.UTF-8"
hopefully it will help someone else...
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How do you validate a URL with a regular expression in Python?
...he result of parsing gives you a netloc or path you don't like, you could call that "invalid".
– S.Lott
Jun 29 '09 at 20:44
2
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