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correct way to use super (argument passing)
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Shouldn't Base call super(Base, self).__init__()?
– cha0site
Jan 23 '12 at 14:47
4
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In which case do you use the JPA @JoinTable annotation?
... project_id
name name task_id
The Project_Tasks table is called a "Join Table". To implement this second solution in JPA you need to use the @JoinTable annotation. For example, in order to implement a uni-directional one-to-many association, we can define our entities as such:
Proj...
What is the difference between .*? and .* regular expressions?
...nsider the input 101000000000100.
Using 1.*1, * is greedy - it will match all the way to the end, and then backtrack until it can match 1, leaving you with 1010000000001.
.*? is non-greedy. * will match nothing, but then will try to match extra characters until it matches 1, eventually matching 101...
Stop pip from failing on single package when installing with requirements.txt
I am installing packages from requirements.txt
6 Answers
6
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When to use NSInteger vs. int
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You usually want to use NSInteger when you don't know what kind of processor architecture your code might run on, so you may for some reason want the largest possible integer type, which on 32 bit systems is just an int, while on a ...
How to get instance variables in Python?
Is there a built-in method in Python to get an array of all a class' instance variables? For example, if I have this code:
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How to count the number of set bits in a 32-bit integer?
...Hamming Weight', 'popcount' or 'sideways addition'.
The 'best' algorithm really depends on which CPU you are on and what your usage pattern is.
Some CPUs have a single built-in instruction to do it and others have parallel instructions which act on bit vectors. The parallel instructions (like x86's ...
Logical operators for boolean indexing in Pandas
...Error: The truth value of an array is ambiguous. Use a.empty, a.any() or a.all().
when used as a boolean value. That's because its unclear when it should be True or False. Some users might assume they are True if they have non-zero length, like a Python list. Others might desire for it to be True ...
Among $_REQUEST, $_GET and $_POST which one is the fastest?
...what my application should do (i.e. one or the other, but not both) : generally speaking :
You should use $_GET when someone is requesting data from your application.
And you should use $_POST when someone is pushing (inserting or updating ; or deleting) data to your application.
Either way, the...
How update the _id of one MongoDB Document?
I want update an _id field of one document. I know it's not a really good pratice. But with some technical reason, I need update it. If I try to update it I get:
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