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Scala best way of turning a Collection into a Map-by-key?
...unction seems to assume that I already have a tuple (m,s), which I don't really get
– oxbow_lakes
Mar 24 '09 at 22:33
2
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How to find the operating system version using JavaScript?
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If you list all of window.navigator's properties using
console.log(navigator);
You'll see something like this
# platform = Win32
# appCodeName = Mozilla
# appName = Netscape
# appVersion = 5.0 (Windows; en-US)
# language = en-US
# ...
Django ManyToMany filter()
...nes__in=[zone1, zone2, zone3])
The double underscore (__) syntax is used all over the place when working with querysets.
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What is a singleton in C#?
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A singleton is a class which only allows one instance of itself to be created - and gives simple, easy access to said instance. The singleton premise is a pattern across software development.
There is a C# implementation "Implementing the Singleton Pattern i...
What does enumerate() mean?
...ieving that; one using itertools.count() to do the counting, the other manually counting in a generator function:
from itertools import count
def enumerate(it, start=0):
# return an iterator that adds a counter to each element of it
return zip(count(start), it)
and
def enumerate(it, sta...
Python: most idiomatic way to convert None to empty string?
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If you actually want your function to behave like the str() built-in, but return an empty string when the argument is None, do this:
def xstr(s):
if s is None:
return ''
return str(s)
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Error to run Android Studio
I have installed Android Studio and I followed all steps described here
17 Answers
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C++11 reverse range-based for-loop
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Actually Boost does have such adaptor: boost::adaptors::reverse.
#include <list>
#include <iostream>
#include <boost/range/adaptor/reversed.hpp>
int main()
{
std::list<int> x { 2, 3, 5, 7, 11, 13, 1...
Dynamically adding a form to a Django formset with Ajax
I want to automatically add new forms to a Django formset using Ajax, so that when the user clicks an "add" button it runs JavaScript that adds a new form (which is part of the formset) to the page.
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In Django - Model Inheritance - Does it allow you to override a parent model's attribute?
...ld instances (at least,
not at the moment). If a base class has a field called author, you
cannot create another model field called author in any class that
inherits from that base class.
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