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Is there a typical state machine implementation pattern?
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Really nice touch how NUM_STATES is defined.
– Albin Stigo
Dec 19 '15 at 19:38
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What's the difference between using CGFloat and float?
I tend to use CGFloat all over the place, but I wonder if I get a senseless "performance hit" with this. CGFloat seems to be something "heavier" than float, right? At which points should I use CGFloat, and what makes really the difference?
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SQLAlchemy IN clause
...w about
session.query(MyUserClass).filter(MyUserClass.id.in_((123,456))).all()
edit: Without the ORM, it would be
session.execute(
select(
[MyUserTable.c.id, MyUserTable.c.name],
MyUserTable.c.id.in_((123, 456))
)
).fetchall()
select() takes two parameters, the first...
Find which version of package is installed with pip
..., is it possible to figure out which version of a package is currently installed?
15 Answers
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How to achieve function overloading in C?
...sociation list that looks a bit like a switch block. _Generic gets the overall type of the expression and then "switches" on it to select the end result expression in the list for its type:
_Generic(1, float: 2.0,
char *: "2",
int: 2,
default: get_two_object());
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Python function attributes - uses and abuses [closed]
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I typically use function attributes as storage for annotations. Suppose I want to write, in the style of C# (indicating that a certain method should be part of the web service interface)
class Foo(WebService):
@webmethod
de...
What is Bit Masking?
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the b to indicate binary literal is not supported by all compilers, correct?
– Ungeheuer
May 8 '17 at 23:37
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Do I need to explicitly call the base virtual destructor?
...the destructor again as virtual on the inheriting class, but do I need to call the base destructor?
7 Answers
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Is module __file__ attribute absolute or relative?
...a file. The __file__ attribute is not present for C modules that are statically linked into the interpreter; for extension modules loaded dynamically from a shared library, it is the pathname of the shared library file.
From the mailing list thread linked by @kindall in a comment to the question:
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Multiple variables in a 'with' statement?
...textlib.nested, this guarantees that a and b will have their __exit__()'s called even if C() or it's __enter__() method raises an exception.
You can also use earlier variables in later definitions (h/t Ahmad below):
with A() as a, B(a) as b, C(a, b) as c:
doSomething(a, c)
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