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Does SQLAlchemy have an equivalent of Django's get_or_create?
...ject from the database if it already exists (based on provided parameters) or create it if it does not.
9 Answers
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Java logical operator short-circuiting
Which set is short-circuiting, and what exactly does it mean that the complex conditional expression is short-circuiting?
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Datetime - Get next tuesday
...ean by "next Tuesday", but this code gives you "the next Tuesday to occur, or today if it's already Tuesday":
DateTime today = DateTime.Today;
// The (... + 7) % 7 ensures we end up with a value in the range [0, 6]
int daysUntilTuesday = ((int) DayOfWeek.Tuesday - (int) today.DayOfWeek + 7) % 7;
Da...
Check free disk space for current partition in bash
I am writing an installer in bash. The user will go to the target directory and runs the install script, so the first action should be to check that there is enough space. I know that df will report all file systems, but I was wondering if there was a way to get the free space just for the partition...
How to get the type of T from a member of a generic class or method?
Let say I have a generic member in a class or method, so:
16 Answers
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How do I check that a number is float or integer?
How to find that a number is float or integer ?
44 Answers
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To find whether a column exists in data frame or not
... dat and that your column name to check is "d", you can use the %in% operator:
if("d" %in% colnames(dat))
{
cat("Yep, it's in there!\n");
}
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How does the getView() method work when creating your own custom adapter?
...ews, when a View is scrolled so that is no longer visible, it can be used for one of the new Views appearing. This reused View is the convertView. If this is null it means that there is no recycled View and we have to create a new one, otherwise we should use it to avoid creating a new.
3: The pare...
C# short/long/int literal format?
... = 1L; // long
I think that's all... there are no literal specifiers for short/ushort/byte/sbyte
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What happens if you static_cast invalid value to enum class?
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What is color set to according to the standard?
Answering with a quote from the C++11 and C++14 Standards:
[expr.static.cast]/10
A value of integral or enumeration type can be explicitly converted to an enumeration type. The valu...