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What is the purpose of Flask's context stacks?
... up models
db.create_all()
In this case, the Flask-SQLAlchemy extension knows about the app application, but during create_all() it will throw an error complaining about there not being an application context. This error is justified; you never told Flask what application it should be dealing with...
Differences between Oracle JDK and OpenJDK
...arting with JDK 11 accessing the long time support Oracle JDK/Java SE will now require a commercial license. You should now pay attention to which JDK you're installing as Oracle JDK without subscription could stop working. source
Ref: List of Java virtual machines
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Get current date in milliseconds
...d it'll result in a negative value.
For example, if I run that code right now, it'll result in
currentTime = 1357234941
and
currentTime /seconds / minutes / hours / days = years
1357234941 / 60 / 60 / 24 / 365 = 43.037637652207
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GetHashCode Guidelines in C#
...rate with hash tables" or similar. Like most things, GetHashCode is about knowing when to break the rules.
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Age from birthdate in python
...etime
import dateutil
def birthday(date):
# Get the current date
now = datetime.datetime.utcnow()
now = now.date()
# Get the difference between the current date and the birthday
age = dateutil.relativedelta.relativedelta(now, date)
age = age.years
return age
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Does Java have a using statement?
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"Luckily" with Java 7 being available now, this answer is no longer true (and I think that ARM blocks are exactly what using does).
– Joachim Sauer
Aug 24 '11 at 8:32
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Finding index of character in Swift String
... Any other indices can be created using successor or predecessor methods.
Now to help us with indices, there is a set of methods (functions in Swift 1.x):
Swift 4.x
let text = "abc"
let index2 = text.index(text.startIndex, offsetBy: 2) //will call succ 2 times
let lastChar: Character = text[index...
Timer function to provide time in nano seconds using C++
...e QueryPerformanceCounter. And here is more on QPC
Apparently there is a known issue with QPC on some chipsets, so you may want to make sure you do not have those chipset. Additionally some dual core AMDs may also cause a problem. See the second post by sebbbi, where he states:
QueryPerformance...
Measuring execution time of a function in C++
...5;
}
}
int main()
{
auto t1 = std::chrono::high_resolution_clock::now();
function();
auto t2 = std::chrono::high_resolution_clock::now();
auto duration = std::chrono::duration_cast<std::chrono::microseconds>( t2 - t1 ).count();
std::cout << duration;
return...
get client time zone from browser [duplicate]
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TL;DR We now can use Intl.DateTimeFormat().resolvedOptions().timeZone (no IE11) as suggested by Wallace.
– Code4R7
Jul 12 '18 at 17:48
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