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Why is the order in dictionaries and sets arbitrary?
...der:
>>> {'bar': None, 'foo': None}
{'foo': None, 'bar': None}
All slots except 3 and 4 are empty, looping over the table first lists slot 3, then slot 4, so 'foo' is listed before 'bar'.
bar and baz, however, have hash values that are exactly 8 apart and thus map to the exact same slot...
Inheritance and Overriding __init__ in python
...
The book is a bit dated with respect to subclass-superclass calling. It's also a little dated with respect to subclassing built-in classes.
It looks like this nowadays:
class FileInfo(dict):
"""store file metadata"""
def __init__(self, filename=None):
super(FileInfo,...
How to save all the variables in the current python session?
I want to save all the variables in my current python environment. It seems one option is to use the 'pickle' module. However, I don't want to do this for 2 reasons:
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How to find the size of localStorage
...ly developing a site that will make use of HTML5's localStorage. I've read all about the size limitations for different browsers. However, I haven't seen anything on how to find out the current size of a localStorage instance. This question seems to indicate that JavaScript doesn't have a built in...
Fragment Inside Fragment
... current versions of the Android Support package -- or native fragments on API Level 17 and higher -- you can nest fragments, by means of getChildFragmentManager(). Note that this means that you need to use the Android Support package version of fragments on API Levels 11-16, because even though the...
View markdown files offline [closed]
...plug-ins that work well. I've been using Markdown Preview Plus.
After install, enable "Allow access to file URLs" in Extensions (menu > More tools > Extensions or enter URL chrome://extensions/ instead).
Then drag-n-drop a Markdown file onto Chrome and use your favorite editor to edit.
...
How can I test https connections with Django as easily as I can non-https connections using 'runserv
...ifying middleman between your browser and the development server. Stunnel allows you to set up a lightweight server on your machine that accepts connections on a configured port, wraps them with SSL, and passes them along to some other server. We'll use this to open a stunnel port (8443) and pass ...
Define a lambda expression that raises an Exception
...ur goal is to avoid a def, this obviously doesn't cut it. It does, however allow you to conditionally raise exceptions, e.g.:
y = lambda x: 2*x if x < 10 else raise_(Exception('foobar'))
Alternatively you can raise an exception without defining a named function. All you need is a strong stom...
Add and Remove Views in Android Dynamically?
...app like on the original stock Android contacts screen where you press a small icon on the right side of a field and it adds or deletes a field which consists of a TextView and an editTextView (from what I can see).
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When should one use final for method parameters and local variables?
...e set by end of construction, making that field reference immutable. This allows safe publication of fields and can avoid the need for synchronization on later reads. (Note that for an object reference, only the field reference is immutable - things that object reference refers to can still change...