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How to increment a NSNumber
..., with the use of object literals, you can clean the code up even a little bit more...
NSNumber *x = @(1);
x = @([x intValue] + 1);
// x = 2
Still kind of a pain to deal with the boxing and unboxing everything to do simple operations, but it's getting better, or at least shorter.
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How can I use UUIDs in SQLAlchemy?
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answered Mar 21 '18 at 4:10
JDiMatteoJDiMatteo
8,03133 gold badges3939 silver badges5454 bronze badges
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Install a Python package into a different directory using pip?
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@Piotr: yes there is see my answer. Using '--prefix' is a bit coarse, but works nice if you want your pure python to go under /usr/lib/pythonX.Y/site-packages instead of /usr/local/lib/pythonX.Y/site-packages.
– Anthon
Jun 13 '12 at 14:39
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How do I get a value of datetime.today() in Python that is “timezone aware”?
...ay to create aware timezones without creating your own timezone class.
On Windows, there's win32timezone.utcnow(), but that's part of pywin32. I would rather suggest to use the pytz library, which has a constantly updated database of most timezones.
Working with local timezones can be very tricky ...
When would anyone use a union? Is it a remnant from the C-only days?
...ce.
Use case 1: the chameleon
With unions, you can regroup a number of arbitrary classes under one denomination, which isn't without similarities with the case of a base class and its derived classes. What changes, however, is what you can and can't do with a given union instance:
struct Batman;
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How to find all the subclasses of a class given its name?
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10 Answers
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Active
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C# binary literals
...riday
}
Original Post
Since the topic seems to have turned to declaring bit-based flag values in enums, I thought it would be worth pointing out a handy trick for this sort of thing. The left-shift operator (<<) will allow you to push a bit to a specific binary position. Combine that with t...
What is more efficient? Using pow to square or just multiply it with itself?
...0.011254
2.45829e+52
This is on an Intel Core Duo running Ubuntu 9.10 64bit. Compiled using gcc 4.4.1 with -o2 optimization.
So in C, yes x*x*x will be faster than pow(x, 3), because there is no pow(double, int) overload. In C++, it will be the roughly same. (Assuming the methodology in my testi...
How many characters can a Java String have?
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Assuming a 64-bit JVM, since you'd need 8GB of virtual memory to store a string of that length.
– Robert Fraser
Jul 24 '09 at 20:59
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Encode String to UTF-8
...:49
Gray
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answered Apr 20 '11 at 11:58
Joachim Sau...