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std::function vs template
...onst auto tp2 = high_resolution_clock::now();
const auto d = duration_cast<milliseconds>(tp2 - tp1);
std::cout << d.count() << std::endl;
std::cout << result<< std::endl;
return 0;
}
Update:
Added vs2015. I also noticed that there are double->fl...
Android Fragments. Retaining an AsyncTask during screen rotation or configuration change
...ay. I just did it in onAttach() and onDetach() so I could avoid constantly casting the activity to TaskCallbacks every time I wanted to use it.
– Alex Lockwood
Nov 13 '14 at 16:14
...
Referring to the null object in Python
...f not bool(value):
# Do something
None is a "falsey", meaning that if cast to a boolean it will return False and if applied the not operator it will return True. Note however that it's not a property unique to None. In addition to False itself, the property is shared by empty lists, tuples, set...
What are the effects of exceptions on performance in Java?
... with the success object and then doing an "instanceof" check and a couple casts to get the success or failure information.
It turns out that at the risk of type safety, Sentinel values are faster than exceptions, but only by a factor of roughly 2x. Now, that may seem like a lot, but that 2x only c...
Why are Subjects not recommended in .NET Reactive Extensions?
...ibe to (you can use AsObservable() on your subject to make sure nobody can cast to a Subject and mess things up).
You could also achieve this with a .NET event and use FromEventPattern, but if I'm only going to turn the event into an IObservable anyway, I don't see the benefit of having an event i...
Complete Working Sample of the Gmail Three-Fragment Animation Scenario?
...Demo video with the animation is Here (Slow frame rate cause of the screen cast. Actual performance is very fast)
Usage:
layout = new ThreeLayout(this, 3);
layout.setAnimationDuration(1000);
setContentView(layout);
layout.getLeftView(); //<---inflate FragmentA here
layout.getMiddleView(); /...
Why isn't `int pow(int base, int exponent)` in the standard C++ libraries?
...ype, then all arguments corresponding to double parameters are effectively cast to double.
So, basically, integer parameters will be upgraded to doubles to perform the operation.
Prior to C++11 (which was when your question was asked), no integer overloads existed.
Since I was neither closely ...
How should one use std::optional?
...at are provided purely to enforce intention) include the various C++ style casts, "const" (especially on member functions), and the "bool" type, to name a few. Arguably you don't really need these code features, so long as everyone obeys intentions or comments.
...
#define macro for debug printing in C?
...GS__) : 0))
This leaves the program fragment shown as valid. The (void) cast prevents it being used in contexts where a value is required — but it could be used as the left operand of a comma operator where the do { ... } while (0) version cannot. If you think you should be able to embed debug...
Java 8 Iterable.forEach() vs foreach loop
...ator) and cannot be used in a for-each, only with a forEach(). I recommend casting Streams into Iterables with (Iterable<T>)stream::iterator. A better alternative is to use StreamEx which fixes a number of Stream API problems, including implementing Iterable.
That said, forEach() is useful for...