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Why doesn't JavaScript have a last method? [closed]
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answered Aug 21 '12 at 18:05
Pablo DiazPablo Diaz
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Event system in Python
...el is basically a bag-of-handlers with more features related to threading, error handling, ...
python-dispatch requires the even source classes to derive from pydispatch.Dispatcher.
buslane is class-based, supports single- or multiple handlers and facilitates extensive type hints.
Pithikos' Observer...
How to pass a user defined argument in scrapy spider
...able to access it outside the __init__ method. Python throws a not defined error. BTW, why have you omitted the super call? PS. I'm working with the CrawlSpider class
– Birla
Sep 24 '14 at 10:57
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How to determine CPU and memory consumption from inside a process?
...y (PDH), which is a bit "unintuitive" and takes a lot of painful trial and error to get to work. (At least it took me quite a while, perhaps I've been only a bit stupid...)
Note: for clarity all error checking has been omitted from the following code. Do check the return codes...!
Total Virtual...
Python: fastest way to create a list of n lists
...eration, which incurs considerable overhead overhead.
Regardless, [[] for _dummy in xrange(n)] is the right way to do it and none of the tiny (if existent at all) speed differences between various other ways should matter. Unless of course you spend most of your time doing this - but in that case, ...
What is the difference between LR, SLR, and LALR parsers?
...h it, and that count is needed for the L(AL)R versions in practice anyway.
ERROR: If neither SHIFT nor REDUCE is possible, a syntax error is declared.
So, if they all the use the same machinery, what's the point?
The purported value in SLR is its simplicity in implementation; you don't have to sc...
Is bool a native C type?
...p;boolArray[123]).
– Dai
Apr 5 at 0:05
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join list of lists in python [duplicate]
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import itertools
a = [['a','b'], ['c']]
print(list(itertools.chain.from_iterable(a)))
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Why is it string.join(list) instead of list.join(string)?
...ack_overflow'
Using something else than strings will raise the following error:
TypeError: sequence item 0: expected str instance, int found
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Python Pandas merge only certain columns
...ng this to merge column 'Unique_External_Users' from df2 to df1 but got an error ... "None of [Index(['U', 'n', 'i', 'q', 'u', 'e', '', 'E', 'x', 't', 'e', 'r', 'n', 'a',\n 'l', '', 'U', 's', 'e', 'r', 's'],\n dtype='object')] are in the [columns]" .
– CoolDocMan
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