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Why do you need explicitly have the “self” argument in a Python method?
...quote Peters' Zen of Python. "Explicit is better than implicit."
In Java and C++, 'this.' can be deduced, except when you have variable names that make it impossible to deduce. So you sometimes need it and sometimes don't.
Python elects to make things like this explicit rather than based on a r...
How to override the copy/deepcopy operations for a Python object?
I understand the difference between copy vs. deepcopy in the copy module. I've used copy.copy and copy.deepcopy before successfully, but this is the first time I've actually gone about overloading the __copy__ and __deepcopy__ methods. I've already Googled around and looked through the ...
Create unique constraint with null columns
...(user_id, menu_id, recipe_id), you cannot base CLUSTER on a partial index, and queries without a matching WHERE condition cannot use the partial index. (It seems unlikely you'd want a FK reference three columns wide - use the PK column instead).
If you need a complete index, you can alternatively d...
Why java.lang.Object is not abstract? [duplicate]
...e argued that some of the methods would benefit from this. Take hashCode() and equals() for instance, there would probably have been a lot less frustration around the complexities of these two if they had both been made abstract. This would require developers to figure out how they should be impleme...
Git: “Not currently on any branch.” Is there an easy way to get back on a branch, while keeping the
So I've done some work in the repository and when I'm about to commit I realize that I'm not currently on any branch.
9 Ans...
Very Long If Statement in Python [duplicate]
...r example:
if (abcdefghijklmnopqrstuvwxyz > some_other_long_identifier and
here_is_another_long_identifier != and_finally_another_long_name):
# ... your code here ...
pass
share
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Rails Admin vs. ActiveAdmin [closed]
I've been looking into some rails admin plugins and came across these:
3 Answers
3
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Why don't :before and :after pseudo elements work with `img` elements? [duplicate]
... Note. This specification does not fully define the interaction of :before and :after with replaced elements (such as IMG in HTML). This will be defined in more detail in a future specification.
I guess this means they don't work with img elements (for now).
Also see this answer.
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How to check for file existence [duplicate]
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Check out Pathname and in particular Pathname#exist?.
File and its FileTest module are perhaps simpler/more direct, but I find Pathname a nicer interface in general.
s...
What is the difference between List and ArrayList? [duplicate]
I've been using ArrayList recently in my android project at the office and I'm a bit confused between List and ArrayList, what is the difference of the two and what should I use?
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