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How would I run an async Task method synchronously?
I'm learning about async/await, and ran into a situation where I need to call an async method synchronously. How can I do that?
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Does SQLAlchemy have an equivalent of Django's get_or_create?
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That's basically the way to do it, there is no shortcut readily available AFAIK.
You could generalize it ofcourse:
def get_or_create(session, model, defaults=None, **kwargs):
instance = session.query(model).filter_by(**kwargs).firs...
How to get the name of enumeration value in Swift?
... on each case to return a string literal. In addition, this works automatically for any enum, even if no raw-value type is specified.
debugPrint(_:) & String(reflecting:) can be used for a fully-qualified name:
debugPrint(city)
// prints "App.City.Melbourne" (or similar, depending on the full ...
How to avoid 'cannot read property of undefined' errors?
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Catching all exceptions without re-throwing is bad, and generally using exceptions as part of the expected flow of execution is also not great -- even though in this case it's pretty well contained.
– hugo
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Could not locate Gemfile
...application on my server using Ruby, Gems, and Bundler. I am trying to install another Ruby on under a different user account but on the same VPS. When I go to run
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Difference between Mock / Stub / Spy in Spock test framework
... replacing a real one, returning something like null or 0 for each method call. You use a mock if you need a dummy instance of a complex class which would otherwise use external resources like network connections, files or databases or maybe use dozens of other objects. The advantage of mocks is tha...
Are tuples more efficient than lists in Python?
...l be more like the tuple example above than the list example, but do you really believe that means performance will be similar?
– mzz
Jan 31 '10 at 15:21
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What does the exclamation mark mean in a Haskell declaration?
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It's a strictness declaration. Basically, it means that it must be evaluated to what's called "weak head normal form" when the data structure value is created. Let's look at an example, so that we can see just what this means:
data Foo = Foo Int Int !Int !(May...
What characters are allowed in DOM IDs? [duplicate]
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Actually there is a difference between HTML and XHTML.
As XHTML is XML the rules for XML IDs apply:
Values of type ID MUST match the Name production.
NameStartChar ::= ":" | [A-Z] | "_" | [a-z] | [#xC0-#xD6] |
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Double vs. BigDecimal?
...tudes (say d1=1000.0 and d2=0.001) could result in the 0.001 being dropped alltogether when summing as the difference in magnitude is so large. With BigDecimal this would not happen.
The disadvantage of BigDecimal is that it's slower, and it's a bit more difficult to program algorithms that way (du...