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Checking for empty queryset in Django
...if not my_objects: to demonstrate that this is how they do it in the docs. All else is utterly irrelevant so I do not get your point. They could as well make a thousand queries and it would still be totally irrelevant as this is not the point of this answer, with which I make clear that I agree.
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Cannot kill Python script with Ctrl-C
...you can't do anything with it after it exits. The process will finish when all non-daemon threads have finished; parent-child relationships don't come into that.
– Thomas K
Dec 6 '13 at 22:22
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How to remove from a map while iterating it?
...= m.erase(it)" since C++11
}
else
{
++it;
}
}
Note that we really want an ordinary for loop here, since we are modifying the container itself. The range-based loop should be strictly reserved for situations where we only care about the elements. The syntax for the RBFL makes this clear...
Qt: can't find -lGL error
I just reinstalled QtCreator, created new project ( Qt Application ) an got this after compilation:
8 Answers
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Best way to iterate through a Perl array
...ay elements occurs. ($_ is aliased to the element in #1, but #2 and #3 actually copy the scalars from the array.)
#5 might be similar.
In terms memory usage: They're all the same except for #5.
for (@a) is special-cased to avoid flattening the array. The loop iterates over the indexes of the array...
How to determine whether code is running in DEBUG / RELEASE build?
...EBUG changed to another variable name such as DEBUG_MODE.
then conditionally code for DEBUG in your source files
#ifdef DEBUG
// Something to log your sensitive data here
#else
//
#endif
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Detecting endianness programmatically in a C++ program
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Is this solution really portable? What if CHAR_BIT != 8 ?
– zorgit
May 30 '15 at 20:12
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Most efficient way to determine if a Lua table is empty (contains no entries)?
...olution though, and I honestly can't assume that my solution is faster overall.
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Is there a “goto” statement in bash?
...atement in bash ? I know It is considered bad practice, but I need specifically "goto".
12 Answers
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What Automatic Resource Management alternatives exist for Scala?
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For now Scala 2.13 has finally supported: try with resources by using Using :), Example:
val lines: Try[Seq[String]] =
Using(new BufferedReader(new FileReader("file.txt"))) { reader =>
Iterator.unfold(())(_ => Option(reader.readLine()).ma...