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When is “i += x” different from “i = i + x” in Python?
...This depends entirely on the object i.
+= calls the __iadd__ method (if it exists -- falling back on __add__ if it doesn't exist) whereas + calls the __add__ method1 or the __radd__ method in a few cases2.
From an API perspective, __iadd__ is supposed to be used for modifying mutable objects i...
How do I create a namespace package in Python?
...you want to release related libraries as separate downloads. For example, with the directories Package-1 and Package-2 in PYTHONPATH ,
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Understanding the main method of python [duplicate]
...roach to "main" is almost unique to the language(*).
The semantics are a bit subtle. The __name__ identifier is bound to the name of any module as it's being imported. However, when a file is being executed then __name__ is set to "__main__" (the literal string: __main__).
This is almost always ...
How can I swap positions of two open files (in splits) in vim?
Assume I've got some arbitrary layout of splits in vim.
12 Answers
12
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Can modules have properties the same way that objects can?
With python properties, I can make it such that
6 Answers
6
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C/C++ line number
...func__ : function name (this is part of C99, not all C++ compilers support it)
__DATE__ : a string of form "Mmm dd yyyy"
__TIME__ : a string of form "hh:mm:ss"
Your code will be :
if(!Logical)
printf("Not logical value at line number %d in file %s\n", __LINE__, __FILE__);
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How to print instances of a class using print()?
...rint(t)
member of Test
The __str__ method is what happens when you print it, and the __repr__ method is what happens when you use the repr() function (or when you look at it with the interactive prompt). If this isn't the most Pythonic method, I apologize, because I'm still learning too - but it w...
what does the __file__ variable mean/do?
I usually just hard-wire these with the actual path. But there is a reason for these statements that determine path at runtime, and I would really like to understand the os.path module so that I can start using it.
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KIO4_Gradient 拓展：布局中的颜色渐变 - App Inventor 2 中文网 - 清泛IT...
...置255彻底成白色了。
暂时用拓展解决一下：https://community.appinventor.mi ... with-colors/56116/2
Why aren't superclass __init__ methods automatically invoked?
Why did the Python designers decide that subclasses' __init__() methods don't automatically call the __init__() methods of their superclasses, as in some other languages? Is the Pythonic and recommended idiom really like the following?
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