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What is the purpose of the var keyword and when should I use it (or omit it)?
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Django filter queryset __in for *every* item in list
... comments, to add .filter() for each category. Each additional filter adds more joins, which should not be a problem for small set of categories.
There is the aggregation approach. This query would be shorter and perhaps quicker for a large set of categories.
You also have the option of using cust...
Meaning of acronym SSO in the context of std::string
... fixed at compile time, but the size of arrays from the free store is not. Moreover, the stack size is limited (typically a few MiB), whereas the free store is only limited by your system's memory.
SSO is the Short / Small String Optimization. A std::string typically stores the string as a pointer ...
Checking network connection
...on, the DNS lookup itself may block the call to urllib_request.urlopen for more than a second. Thanks to @rzetterberg for pointing this out.
If the fixed IP address above is not working, you can find a current IP address for google.com (on unix) by running
% dig google.com +trace
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google.co...
How to template If-Else structures in data-bound views?
...kout-switch-case) is quite flexible and can let you easily handle this and more complicated ones (more states than true/false).
Another option is to use dynamic templates. You would bind an area to one or more templates with the template name being used based on an observable. Here is a post that ...
Problem with converting int to string in Linq to entities
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How to enumerate an object's properties in Python?
...he object's setter (and/or its parents'). It's quite common in python that more things than meet the eye are happening in the background during attribute setting (e.g. sanitation), using setattr() ensures that you don't miss out, or are forced to handle them explicitly yourself.
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Adding devices to team provisioning profile
...matic device provisioning isn't as easy turning it on/off but you can read more here: developer.apple.com/library/ios/qa/qa1814/_index.html
– thattyson
Nov 11 '15 at 0:13
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Is Meyers' implementation of the Singleton pattern thread safe?
...scusses thread safe implementations of the pattern, and the conclusion is, more or less, that (in C++03) full locking around the instantiating method is basically the simplest way to ensure proper concurrency on all platforms, while most forms of double-checked locking pattern variants may suffer fr...
Mercurial: how to amend the last commit?
...1 undo the last (1) commit(s), so you can do it again (see this answer for more information).
Using the MQ extension, which is shipped with Mercurial
Even if it isn't shipped with Mercurial, the Histedit extension is worth mentioning
You can also have a look on the Editing History page of the Mer...