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What is the difference between .*? and .* regular expressions?
...edy, first tries to match as many . as possible.
eeeAiiZuuuuAoooZeeee
\_______________/
A.* matched, Z can't match
Since the Z doesn't match, the engine backtracks, and .* must then match one fewer .:
eeeAiiZuuuuAoooZeeee
\______________/
A.* matched, Z still can't match
This ha...
Why is Python running my module when I import it, and how do I stop it?
...is:
# stuff to run always here such as class/def
def main():
pass
if __name__ == "__main__":
# stuff only to run when not called via 'import' here
main()
See What is if __name__ == "__main__" for?
It does require source control over the module being imported, however.
Happy coding.
...
Accessing dict keys like an attribute?
...
The best way to do this is:
class AttrDict(dict):
def __init__(self, *args, **kwargs):
super(AttrDict, self).__init__(*args, **kwargs)
self.__dict__ = self
Some pros:
It actually works!
No dictionary class methods are shadowed (e.g. .keys() work just fine. Unle...
Clang vs GCC for my Linux Development project
...inux-gnu/4.3.4/include/g++-v4/ostream:112: note: candidates are: std::basic_ostream<_CharT, _Traits>& std::basic_ostream<_CharT, _Traits>::operator<<(std::basic_ostream<_CharT, _Traits>& (*)(std::basic_ostream<_CharT, _Traits>&)) [with _CharT = char, _Traits...
What is the meaning of single and double underscore before an object name?
...owever, nothing special is done with the name itself.
To quote PEP-8:
_single_leading_underscore: weak "internal use" indicator. E.g. from M import * does not import objects whose name starts with an underscore.
Double Underscore (Name Mangling)
From the Python docs:
Any identifier of th...
Define a lambda expression that raises an Exception
...
There is more than one way to skin a Python:
y = lambda: (_ for _ in ()).throw(Exception('foobar'))
Lambdas accept statements. Since raise ex is a statement, you could write a general purpose raiser:
def raise_(ex):
raise ex
y = lambda: raise_(Exception('foobar'))
But if...
Get absolute path of initially run script
...
The correct solution is to use the get_included_files function:
list($scriptPath) = get_included_files();
This will give you the absolute path of the initial script even if:
This function is placed inside an included file
The current working directory is dif...
How to fix “Attempted relative import in non-package” even with __init__.py
...
Yes. You're not using it as a package.
python -m pkg.tests.core_test
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How to return a value from __init__ in Python?
I have a class with an __init__ function.
10 Answers
10
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Concurrent HashSet in .NET Framework?
...byte (1 byte in memory).
private ConcurrentDictionary<string, byte> _data;
This is the recommended option because the type is thread-safe and provide you the same advantages than a HashSet<T> except key and value are different objects.
Source: Social MSDN
ConcurrentBag
If you don't...