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If list index exists, do X
... that relative index from the end of the list...
However, by definition, all items in a Python list between 0 and len(the_list)-1 exist (i.e., there is no need for a try, except if you know 0 <= index < len(the_list)).
You can use enumerate if you want the indexes between 0 and the last el...
In which order do CSS stylesheets override?
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Actually, !important participates directly in the cascade, and has nothing to do with specificity. Specificity is related to selectors, whereas !important is used with property declarations. (So you're right in saying that the ru...
Rails: How to reference images in CSS within Rails 4
... don't have the proper name adjusted. Here's what I mean. I have a file called logo.png. Yet when it shows up on heroku it is viewed as:
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How to move a git repository into another directory and make that directory a git repository?
...create it)
$ cp -r gitrepo1 newrepo
# remove .git from old repo to delete all history and anything git from it
$ rm -rf gitrepo1/.git
Note that the copy is quite expensive if the repository is large and with a long history. You can avoid it easily too:
# move the directory instead
$ mv gitrepo1 ...
Why does std::getline() skip input after a formatted extraction?
..., it follows that it must be skipped or ignored somehow. One option is to call std::cin.ignore() after the the first extraction. It will discard the next available character so that the newline is no longer in the way.
std::getline(std::cin.ignore(), state)
In-Depth Explanation:
This is the overlo...
What is the purpose of backbone.js?
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Backbone.js is basically an uber-light framework that allows you to structure your Javascript code in an MVC (Model, View, Controller) fashion where...
Model is part of your code that retrieves and populates the data,
View is the HTML repres...
Deep copying an NSArray
Is there any built-in function that allows me to deep copy an NSMutableArray ?
6 Answers
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Difference between Select and ConvertAll in C#
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Select is a LINQ extension method and works on all IEnumerable<T> objects whereas ConvertAll is implemented only by List<T>. The ConvertAll method exists since .NET 2.0 whereas LINQ was introduced with 3.5.
You should favor Select over ConvertAll as it works ...
Remove non-numeric characters (except periods and commas) from a string
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You could use preg_replace to swap out all non-numeric characters and the comma and period/full stop as follows:
$testString = '12.322,11T';
echo preg_replace('/[^0-9,.]+/', '', $testString);
The pattern can also be expressed as /[^\d,.]+/
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Difference between static STATIC_URL and STATIC_ROOT on Django
...example.com/static/"
now the command ./manage.py collectstatic will copy all the static files(ie in static folder in your apps, static files in all paths) to the directory /var/www/example.com/static/. now you only need to serve this directory on apache or nginx..etc.
STATIC_URL
The URL of w...