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Multiple levels of 'collection.defaultdict' in Python
... @ScienceFriction Anything specific that you need help with? When d[new_key] is accessed, it will call the lambda which will create a new defaultdict(int). And when d[existing_key][new_key2] is accessed, a new int will be created.
– interjay
Oct 11 '13 at 1...
How to get a complete list of object's methods and attributes?
...nts accepted by the getattr built-in function. As the user can reimplement __getattr__, suddenly allowing any kind of attribute, there is no possible generic way to generate that list. The dir function returns the keys in the __dict__ attribute, i.e. all the attributes accessible if the __getattr__ ...
Get the name of the currently executing method
...
Even better than my first answer you can use __method__:
class Foo
def test_method
__method__
end
end
This returns a symbol – for example, :test_method. To return the method name as a string, call __method__.to_s instead.
Note: This requires Ruby 1.8.7.
...
Why does the C preprocessor interpret the word “linux” as the constant “1”?
...whether it's being compiled for a Linux target or not it can check whether __linux__ is defined (assuming you're using gcc or a compiler that's compatible with it). See the GNU C preprocessor manual for more information.
A largely irrelevant aside: the "Best One Liner" winner of the 1987 Internatio...
what does the __file__ variable mean/do?
...
When a module is loaded from a file in Python, __file__ is set to its path. You can then use that with other functions to find the directory that the file is located in.
Taking your examples one at a time:
A = os.path.join(os.path.dirname(__file__), '..')
# A is the par...
Checking if an instance's class implements an interface?
...
As therefromhere points out, you can use class_implements(). Just as with Reflection, this allows you to specify the class name as a string and doesn't require an instance of the class:
interface IInterface
{
}
class TheClass implements IInterface
{
}
$interfaces = cl...
Difference between except: and except Exception as e: in Python
...
['__cause__', '__class__', '__context__', '__delattr__', '__dict__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__le__', '__lt__', '__ne__...
correct way to use super (argument passing)
...ich unlike object, absorbs/ignores arguments:
class Base(object):
def __init__(self, *args, **kwargs): pass
class A(Base):
def __init__(self, *args, **kwargs):
print "A"
super(A, self).__init__(*args, **kwargs)
class B(Base):
def __init__(self, *args, **kwargs):
...
UML class diagram enum
...
They are simply showed like this:
_______________________
| <<enumeration>> |
| DaysOfTheWeek |
|_____________________|
| Sunday |
| Monday |
| Tuesday |
| ... |
|____________________...
Object of custom type as dictionary key
...
You need to add 2 methods, note __hash__ and __eq__:
class MyThing:
def __init__(self,name,location,length):
self.name = name
self.location = location
self.length = length
def __hash__(self):
return hash((self.name...