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What is the difference between class and instance attributes?
...just look in each instance's __dict__ and the class's __dict__. It just usually doesn't matter very much whether immutable types are shared or not.
– abarnert
Oct 29 '14 at 22:58
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What is uint_fast32_t and why should it be used instead of the regular int and uint32_t?
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int may be as small as 16 bits on some platforms. It may not be sufficient for your application.
uint32_t is not guaranteed to exist. It's an optional typedef that the implementation must provide iff it has an unsigned integer type of exactl...
How do I get the real .height() of a overflow: hidden or overflow: scroll div?
...qual to the minimum clientHeight the element would require in order to fit all the content in the viewpoint without using a vertical scrollbar. It includes the element padding but not its margin.
share
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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...
Instance attribute attribute_name defined outside __init__
I split up my class constructor by letting it call multiple functions, like this:
6 Answers
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What does “#define _GNU_SOURCE” imply?
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For exact details on what are all enabled by _GNU_SOURCE, documentation can help.
From the GNU documentation:
Macro: _GNU_SOURCE
If you define this macro, everything is included: ISO C89, ISO C99, POSIX.1, POSIX.2, BSD, SVID, X/Open, LFS, and ...
How to reliably open a file in the same directory as a Python script
...th(
os.path.join(os.getcwd(), os.path.dirname(__file__)))
The join() call prepends the current working directory, but the documentation says that if some path is absolute, all other paths left of it are dropped. Therefore, getcwd() is dropped when dirname(__file__) returns an absolute path.
Als...
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 ...
std::vector performance regression when enabling C++11
I have found an interesting performance regression in a small C++ snippet, when I enable C++11:
1 Answer
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