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Define css class in django Forms
... The only sane solution, I must say. Thank you!. Python code, and especially in form's definition, is the last place to put stuff for styling - these definitely belong to the templates.
– Boris Chervenkov
Nov 12 '11 at 23:09
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How do I check if a string is a number (float)?
...r.
I'm not sure that anything much could be faster than the above. It calls the function and returns. Try/Catch doesn't introduce much overhead because the most common exception is caught without an extensive search of stack frames.
The issue is that any numeric conversion function has two kin...
Is it possible to declare two variables of different types in a for loop?
...and clang for years (since gcc-7 and clang-4.0) (clang live example). This allows us to unpack a tuple like so:
for (auto [i, f, s] = std::tuple{1, 1.0, std::string{"ab"}}; i < N; ++i, f += 1.5) {
// ...
}
The above will give you:
int i set to 1
double f set to 1.0
std::string s set to "...
How to run a program without an operating system?
How do you run a program all by itself without an operating system running?
Can you create assembly programs that the computer can load and run at startup, e.g. boot the computer from a flash drive and it runs the program that is on the CPU?
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What is your favorite C programming trick? [closed]
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C99 offers some really cool stuff using anonymous arrays:
Removing pointless variables
{
int yes=1;
setsockopt(yourSocket, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int));
}
becomes
setsockopt(yourSocket, SOL_SOCKET, SO_REUSEADDR...
How do I clear only a few specific objects from the workspace?
I would like to remove some data from the workspace. I know the "Clear All" button will remove all data. However, I would like to remove just certain data.
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Why are all fields in an interface implicitly static and final?
I am just trying to understand why all fields defined in an Interface are implicitly static and final . The idea of keeping fields static makes sense to me as you can't have objects of an interface but why they are final (implicitly)?
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Parse config files, environment, and command-line arguments, to get a single collection of options
...d-line argument parsing ( argparse ). I want to write a program that does all those, and also:
11 Answers
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detach all packages while working in R
...*) is not necessary but can be useful to prevent the NULL reply from vertically spamming the R window.
(edit: 9/20/2019) In version 3.6.1
It may be helpful to convert loaded only names(sessionInfo()$loadedOnly) to explicitly attached packages first, and then detach the packages, as so.
lapply(names(...
performSelector may cause a leak because its selector is unknown
...for the C function pointer for the method corresponding to the controller. All NSObjects respond to methodForSelector:, but you can also use class_getMethodImplementation in the Objective-C runtime (useful if you only have a protocol reference, like id<SomeProto>). These function pointers are ...