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How to add property to a class dynamically?
...ibute, on a given class. Kinda like a way to factor a huge if tree out of __getattribute__.
When I ask for foo.b in the example above, Python sees that the b defined on the class implements the descriptor protocol—which just means it's an object with a __get__, __set__, or __delete__ method. Th...
WebClient vs. HttpWebRequest/HttpWebResponse
...the WebClient class. I read somewhere that WebClient is a high-level wrapper for WebRequest/Response .
So far, I can't see anything that can be accomplished with HttpWebRequest/Response that can not be accomplished with WebClient , nor where HttpWebRequest/Response will give you more "fin...
What does it mean if a Python object is “subscriptable” or not?
...
It basically means that the object implements the __getitem__() method. In other words, it describes objects that are "containers", meaning they contain other objects. This includes strings, lists, tuples, and dictionaries.
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Are there legitimate uses for JavaScript's “with” statement?
... same technique used elsewhere - the Chromium source code!
InjectedScript._evaluateOn = function(evalFunction, object, expression) {
InjectedScript._ensureCommandLineAPIInstalled();
// Surround the expression in with statements to inject our command line API so that
// the window object...
Wait for a void async method
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await Task.Run(() => An_async_void_method_I_can_not_modify_now())
– themefield
Mar 12 '19 at 21:46
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Is gcc 4.8 or earlier buggy about regular expressions?
....
Seriously though, who though that shipping an implementation of regex_search that only does "return false" was a good idea?
It wasn't such a bad idea a few years ago, when C++0x was still a work in progress and we shipped lots of partial implementations. No-one thought it would remain unusab...
Explicitly select items from a list or tuple
... myBigList[i] for i in [87, 342, 217, 998, 500] ]
20.6 usec: map(myBigList.__getitem__, (87, 342, 217, 998, 500))
22.7 usec: itemgetter(87, 342, 217, 998, 500)(myBigList)
24.6 usec: list( myBigList[i] for i in [87, 342, 217, 998, 500] )
Note that in Python 3, the 1st was changed to be the same as ...
Relative paths in Python
..., you want to do something like this:
import os
dirname = os.path.dirname(__file__)
filename = os.path.join(dirname, 'relative/path/to/file/you/want')
This will give you the absolute path to the file you're looking for. Note that if you're using setuptools, you should probably use its package re...
Check if something is (not) in a list in Python
... @nightcracker That makes no sense as A not in B is reduced to doing not B.__contains__(A) which is the same as what not A in B is reduced to which is not B.__contains__(A).
– Dan D.
May 2 '12 at 0:33
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What is the most pythonic way to check if an object is a number?
...: 0 + x
except TypeError: canadd=False
else: canadd=True
The presence of __add__ per se tells you nothing useful, since e.g all sequences have it for the purpose of concatenation with other sequences. This check is equivalent to the definition "a number is something such that a sequence of such t...