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Does Flask support regular expressions in its URL routing?
...will be evaluated directly at runtime. This shouldn't be problematic for smaller apps (or apps that reuse regex's multiple times, I'd think) as the last couple of regex patterns are stored compiled in memory.
– bbenne10
Jul 18 '13 at 14:13
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Why does using an Underscore character in a LIKE filter give me all the results?
...t end with 'abc'.
In your case you have searched by '%_%'. This will give all the rows with that column having one or more characters, that means any characters, as its value. This is why you are getting all the rows even though there is no _ in your column values.
...
What is the best way to compute trending topics or tags?
...
This problem calls for a z-score or standard score, which will take into account the historical average, as other people have mention, but also the standard deviation of this historical data, making it more robust than just using the avera...
Performance difference for control structures 'for' and 'foreach' in C#
...t will depend on whether you're doing any real work in the loop. In almost all cases, the difference to performance won't be significant, but the difference to readability favours the foreach loop.
I'd personally use LINQ to avoid the "if" too:
foreach (var item in list.Where(condition))
{
}
EDI...
Does python have an equivalent to Java Class.forName()?
...takes a fully qualified class name and returns the class, however you have all the pieces needed to build that, and you can connect them together.
One bit of advice though: don't try to program in Java style when you're in python.
If you can explain what is it that you're trying to do, maybe we ca...
__getattr__ on a module
...
A while ago, Guido declared that all special method lookups on
new-style classes bypass __getattr__ and __getattribute__. Dunder methods had previously worked on modules - you could, for example, use a module as a context manager simply by defining __enter__...
if A vs if A is not None:
...
The statement
if A:
will call A.__nonzero__() (see Special method names documentation) and use the return value of that function. Here's the summary:
object.__nonzero__(self)
Called to implement truth value testing and the built-in operation ...
How do I create a constant in Python?
.... This is the closest equivalent to Java's final. However, it does not actually prevent reassignment:
from typing import Final
a: Final = 1
# Executes fine, but mypy will report an error if you run mypy on this:
a = 2
sha...
What is the difference between class and instance attributes?
...just look in each instance's __dict__ and the class's __dict__. It just usually doesn't matter very much whether immutable types are shared or not.
– abarnert
Oct 29 '14 at 22:58
1...
Does Python support short-circuiting?
...circuiting "executed" not printed
1
>>> 1 and fun(1) # fun(1) called and "executed" printed
executed
1
>>> 0 and fun(1) # due to short-circuiting "executed" not printed
0
Note: The following values are considered by the interpreter to mean false:
False None ...