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What does the slash mean in help() output?
...python functions.
Also see the Argument Clinic documentation:
To mark all parameters as positional-only in Argument Clinic, add a / on a line by itself after the last parameter, indented the same as the parameter lines.
and the (very recent addition to) the Python FAQ:
A slash in the argu...
How to avoid isset() and empty()
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For those interested, I have expanded this topic into a small article, which provides the below information in a somewhat better structured form: The Definitive Guide To PHP's isset And empty
IMHO you should think about not just making the app "E_NOTICE compatible", but restructu...
Empty set literal?
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Actually, set literals have been backported to Python 2.7, so they are not only available strictly in Python 3.
– Jim Brissom
May 25 '11 at 20:56
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Reading a huge .csv file
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You are reading all rows into a list, then processing that list. Don't do that.
Process your rows as you produce them. If you need to filter the data first, use a generator function:
import csv
def getstuff(filename, criterion):
with ...
sys.argv[1] meaning in script
...more tutorial level.
For every invocation of Python, sys.argv is automatically a list of strings representing the arguments (as separated by spaces) on the command-line. The name comes from the C programming convention in which argv and argc represent the command line arguments.
You'll want to lea...
In Python, how do I read the exif data for an image?
...e. Some images are generated without EXIF data. If it is empty programmatically, try opening the image file in a photo editing software to check if it actually has EXIF data.
– Gino Mempin
Sep 6 at 0:03
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What are the rules about using an underscore in a C++ identifier?
...FC background, you'll probably use m_foo . I've also seen myFoo occasionally.
5 Answers
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Where can I get a list of Ansible pre-defined variables?
...h0.ipv4.address. Googleing and searching the docs I cound't find a list of all available variables. Would someone list them for me?
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How to backup a local Git repository?
I am using git on a relatively small project and I find that zipping the .git directory's contents might be a fine way to back up the project. But this is kind of weird because, when I restore, the first thing I need to do is git reset --hard .
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How to convert CFStringRef to NSString?
...n objects with +1 reference counts, meaning that they need to be released (all CF[Type]Create format functions do this).
The nice thing is that in Cocoa you can safely use autorelease or release to free them up.
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