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What characters are valid for JavaScript variable names?
...ou an idea of how wrong Anthony Mills' answer is: if you were to summarize all these rules in a single ASCII-only regular expression for JavaScript, it would be 11,236 characters long. Here it is:
// ES5.1 / Unicode 6.1
/^(?!(?:do|if|in|for|let|new|try|var|case|else|enum|eval|false|null|this|true|v...
How exactly do Django content types work?
...t is a "compromise" of sorts to bypass some of the rigid fundamentals of a table oriented SQL system. Do not prematurely optimize your app! Django is best at getting out of your way so you can write the next generation application you have always wanted: use it's features to your advantage!
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PHP mkdir: Permission denied problem
...te permissions on the directory.
Here's what you do in Ubuntu
Make sure all files are owned by the Apache group and user. In Ubuntu it is the www-data group and user
chown -R www-data:www-data /path/to/webserver/www
Next enabled all members of the www-data group to read and write files
chmod -R...
python setup.py uninstall
I have installed a python package with python setup.py install .
16 Answers
16
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BeanFactory vs ApplicationContext
... are great on this: 3.8.1. BeanFactory or ApplicationContext?.
They have a table with a comparison, I'll post a snippet:
Bean Factory
Bean instantiation/wiring
Application Context
Bean instantiation/wiring
Automatic BeanPostProcessor registration
Automatic BeanFactoryPostProcessor registratio...
Best way to merge two maps and sum the values of same key?
...mutable.Map[Int,Int] = Map(1 -> 109, 3 -> 300, 2 -> 20)
Specifically, the binary operator for Map[K, V] combines the keys of the maps, folding V's semigroup operator over any duplicate values. The standard semigroup for Int uses the addition operator, so you get the sum of values for eac...
Open link in new tab or window [duplicate]
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It shouldn't be your call to decide whether the link should open in a new tab or a new window, since ultimately this choice should be done by the settings of the user's browser. Some people like tabs; some like new windows.
Using _blank will tell...
Why do you need explicitly have the “self” argument in a Python method?
... to make things like this explicit rather than based on a rule.
Additionally, since nothing is implied or assumed, parts of the implementation are exposed. self.__class__, self.__dict__ and other "internal" structures are available in an obvious way.
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How to convert a std::string to const char* or char*?
... Notice that the above is not exception safe. If anything between the new call and the delete call throws, you will leak memory, as nothing will call delete for you automatically. There are two immediate ways to solve this.
boost::scoped_array
boost::scoped_array will delete the memory for you upo...
Find an item in List by LINQ?
Here I have a simple example to find an item in a list of strings. Normally I use for loop or anonymous delegate to do it like this:
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