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Python read-only property
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Generally, Python programs should be written with the assumption that all users are consenting adults, and thus are responsible for using things correctly themselves. However, in the rare instance where it just does not make sens...
Do try/catch blocks hurt performance when exceptions are not thrown?
... {
Console.WriteLine(ex.ToString());
}
finally
{
d = Math.Sin(d);
}
}
w.Stop();
Console.Write(" try/catch/finally: ");
Console.WriteLine(w.ElapsedMilliseconds);
w.Reset();
d = 0;
w.Start();
for (int i = ...
C++0x has no semaphores? How to synchronize threads?
...ck Overflow regarding the use of semaphores. I use them (posix semaphores) all the time to let a thread wait for some event in another thread:
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Assigning a variable NaN in python without numpy
...aking) be said to be equal to one another -- see What is the rationale for all comparisons returning false for IEEE754 NaN values? for more details and information.
Instead, use math.isnan(...) if you need to determine if a value is NaN or not.
Furthermore, the exact semantics of the == operation...
Received fatal alert: handshake_failure through SSLHandshakeException
... server's certificate is probably not trusted by the client. This would usually result in a more verbose error, but it is quite possible. Usually the fix is to import the server's CA certificate into the client's trust store.
The cerificate is issued for a different domain. Again, this would have re...
What new capabilities do user-defined literals add to C++?
C++11 introduces user-defined literals which will allow the introduction of new literal syntax based on existing literals ( int , hex , string , float ) so that any type will be able to have a literal presentation.
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super() fails with error: TypeError “argument 1 must be type, not classobj” when parent does not inh
...ss. Change it like so:
class B(object):
and it will work.
super() and all subclass/superclass stuff only works with new-style classes. I recommend you get in the habit of always typing that (object) on any class definition to make sure it is a new-style class.
Old-style classes (also known as...
How does Django's Meta class work?
I am using Django which allows people to add extra parameters to a class by using class Meta .
6 Answers
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Why is it slower to iterate over a small string than a small list?
...nd with timeit and noticed that doing a simple list comprehension over a small string took longer than doing the same operation on a list of small single character strings. Any explanation? It's almost 1.35 times as much time.
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When is assembly faster than C?
...hat although that's not entirely false, the cases where assembler can actually be used to generate more performant code are both extremely rare and require expert knowledge of and experience with assembly.
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