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Why aren't python nested functions called closures?
...s in Python, and they match the definition of a closure. So why are they called nested functions instead of closures ?
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Django filter queryset __in for *every* item in list
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Summary:
One option is, as suggested by jpic and sgallen in the 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...
Which method performs better: .Any() vs .Count() > 0?
...le<T> sequence.
For just IEnumerable<T>, then Any() will generally be quicker, as it only has to look at one iteration. However, note that the LINQ-to-Objects implementation of Count() does check for ICollection<T> (using .Count as an optimisation) - so if your underlying data-sou...
jsonify a SQLAlchemy result set in Flask [duplicate]
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It seems that you actually haven't executed your query. Try following:
return jsonify(json_list = qryresult.all())
[Edit]: Problem with jsonify is, that usually the objects cannot be jsonified automatically. Even Python's datetime fails ;)
Wha...
Capturing Groups From a Grep RegEx
...egex="[0-9]+_([a-z]+)_[0-9a-z]*"
for f in $files # unquoted in order to allow the glob to expand
do
if [[ $f =~ $regex ]]
then
name="${BASH_REMATCH[1]}"
echo "${name}.jpg" # concatenate strings
name="${name}.jpg" # same thing stored in a variable
else
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What's the UIScrollView contentInset property for?
... answered Dec 31 '09 at 1:21
jballjball
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What is Autoloading; How do you use spl_autoload, __autoload and spl_autoload_register?
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spl_autoload_register() allows you to register multiple functions (or static methods from your own Autoload class) that PHP will put into a stack/queue and call sequentially when a "new Class" is declared.
So for example:
spl_autoload_register('m...
Add a prefix to all Flask routes
...tant to the route at every definition. Is there a way to do this automatically?
10 Answers
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Performance difference for control structures 'for' and 'foreach' in C#
...t will depend on whether you're doing any real work in the loop. In almost all cases, the difference to performance won't be significant, but the difference to readability favours the foreach loop.
I'd personally use LINQ to avoid the "if" too:
foreach (var item in list.Where(condition))
{
}
EDI...
What is the best way to compute trending topics or tags?
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This problem calls for a z-score or standard score, which will take into account the historical average, as other people have mention, but also the standard deviation of this historical data, making it more robust than just using the avera...