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Get selected subcommand with argparse
...ser.add_subparsers(dest="subparser_name") # this line changed
>>> foo_parser = subparsers.add_parser('foo')
>>> foo_parser.add_argument('-c', '--count')
>>> bar_parser = subparsers.add_parser('bar')
>>> args = parser.parse_args(['-g', 'xyz', 'foo', '--count', '42'...
Is arr.__len__() the preferred way to get the length of an array in Python?
...ples:
my_tuple = (1,2,3,4,5)
len(my_tuple)
# 5
And strings, which are really just arrays of characters:
my_string = 'hello world'
len(my_string)
# 11
It was intentionally done this way so that lists, tuples and other container types or iterables didn't all need to explicitly implement a public...
Best way to test for a variable's existence in PHP; isset() is clearly broken
... This looks a bit ugly to me, but in the case where you're actually checking an array element, it makes much more sense: isset($foo[$bar]) becomes array_key_exists($bar, $foo)
– Arild
Aug 25 '14 at 14:12
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How to set child process' environment variable in Makefile
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I have GNU make 3.81, and all: <\n\t>export PROJ_ROOT=$(CURDIR)<\n\t>echo $(PROJ_ROOT)<\n> outputs the correct expansion for the first row, but only echo for the second one. PROJ_ROOT is not set after running make. Spaces around = gi...
What does $_ mean in PowerShell?
...
This is the variable for the current value in the pipe line, which is called $PSItem in Powershell 3 and newer.
1,2,3 | %{ write-host $_ }
or
1,2,3 | %{ write-host $PSItem }
For example in the above code the %{} block is called for every value in the array. The $_ or $PSItem variable ...
Best way to organize jQuery/JavaScript code (2013) [closed]
...not up to date. I have over 2000 lines of code in a single file, and as we all know this is bad practice, especially when i'm looking through code or adding new features. I want to better organize my code, for now and for the future.
...
How to paste yanked text into the Vim command line
...you know how to use them you cannot live without them.
Registers are basically storage locations for strings. Vim has many registers that work in different ways:
0 (yank register: when you use y in normal mode, without specifying a register, yanked text goes there and also to the default register...
How to encode the filename parameter of Content-Disposition header in HTTP?
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All in all, this is nothing but a link-only answer with 74 upvotes.
– Antti Haapala
Sep 11 '16 at 21:33
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The tilde operator in Python
...a unary operator (taking a single argument) that is borrowed from C, where all data types are just different ways of interpreting bytes. It is the "invert" or "complement" operation, in which all the bits of the input data are reversed.
In Python, for integers, the bits of the twos-complement repr...
Difference between Python's Generators and Iterators
...ry generator is an iterator, but not vice versa. A generator is built by calling a function that has one or more yield expressions (yield statements, in Python 2.5 and earlier), and is an object that meets the previous paragraph's definition of an iterator.
You may want to use a custom iterator, ra...