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In C++, what is a virtual base class?
...r example, let's say we have:
class A
{
public :
foo() ;
int m_iValue ;
} ;
When you'll try to access m_iValue from D, the compiler will protest, because in the hierarchy, it'll see two m_iValue, not one. And if you modify one, say, B::m_iValue (that is the A::m_iValue parent of B...
Cost of exception handlers in Python
...ements:
t = timeit.Timer(stmt=s, setup='a={}'.format(a))
print("a = {}\n{}".format(a,s))
print("%.2f usec/pass\n" % (1000000 * t.timeit(number=100000)/100000))
Result:
a = 1
try:
b = 10/a
except ZeroDivisionError:
pass
0.25 usec/pass
a = 1
if a:
b = 10/a
0.29 ...
Constants in Objective-C
...s instead of #define'd constants is that you can test for equality using pointer comparison (stringInstance == MyFirstConstant) which is much faster than string comparison ([stringInstance isEqualToString:MyFirstConstant]) (and easier to read, IMO).
...
Timeout for python requests.get entire response
...o):
There are other ways to overcome this problem:
1. Use the TimeoutSauce internal class
From: https://github.com/kennethreitz/requests/issues/1928#issuecomment-35811896
import requests from requests.adapters import TimeoutSauce
class MyTimeout(TimeoutSauce):
def __init__(self, *args, **kwarg...
Is sizeof(bool) defined in the C++ language standard?
..., the Standard C++ header files contained a typedef that equated bool with int. In Visual C++ 5.0 and later, bool is implemented as a built-in type with a size of 1 byte. That means that for Visual C++ 4.2, a call of sizeof(bool) yields 4, while in Visual C++ 5.0 and later, the same call yields 1. T...
Collection versus List what should you use on your interfaces?
...d to be easily extensible by subclassing it; it is designed to be fast for internal implementations. You'll notice the methods on it are not virtual and so cannot be overridden, and there are no hooks into its Add/Insert/Remove operations.
This means that if you need to alter the behavior of the c...
PostgreSQL query to return results as a comma separated list
... Note that for me at least, string_agg didn't like taking an int for its first argument so I did something like: string_agg(CAST(id as varchar), ',') instead.
– JZC
Jun 22 '15 at 17:24
...
Display milliseconds in Excel
I am trying to display milliseconds in an Excel macro. I have a column of integers which are timestamps in milliseconds (e.g. 28095200 is 7:48:15.200 am), and I want to make a new column next to it which keeps a running average and displays the time in a hh:mm:ss.000 format.
...
How to make a website secured with https
I have to build a small webapp for a company to maintain their business data... Only those within the company will be using it, but we are planning to host it in public domain, so that the employees can connect to app from various locations. (Till now I have built web apps that are hosted internall...
Is it wrong to use Deprecated methods or classes in Java?
...e the deprecation. The contract of the API method will not change. If some internal data structure changes in favor of a new, better method, there could be a performance impact, but it's quite unlikely.
The funniest deprecation in the Java API, is imo, the FontMetrics.getMaxDecent. Reason for dep...