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How expensive is RTTI?
...;typeid()
5) 14,261,000 Ticks (~23 Seconds) - typeid() with extra variable allocations.
So the conclusion would be:
For simple cast cases without optimisation typeid() is more than twice faster than dyncamic_cast.
On a modern machine the difference between the two is about 1 nanosecond (a milliont...
What optimizations can GHC be expected to perform reliably?
...pose of floatInwards is floating into branches of a case, so that we don't allocate things, save them on the stack, and then discover that they aren't needed in the chosen branch.
As an example, suppose we had this expression:
let x = big in
case v of
True -> x + 1
False -&g...
Approximate cost to access various caches and main memory?
...s PINNED MEMORY for all CUDA Contexts, not just the one, current, when the allocation was performed
| ___HostAllocWriteCombined_MEM / cudaHostFree() +---------------- cudaHostRegisterMapped -- maps memory allocation into the CUD...
Why do we copy then move?
... a raw C string, a std::string will be constructed, then copied again: two allocations.
There is the C++03 method of taking a reference to a std::string, then swapping it into a local std::string:
struct S
{
std::string data;
S(std::string& str)
{
std::swap(data, str);
}
};
that...
What are the effects of exceptions on performance in Java?
... way to avoid the "rock and hard place" choice you present here, is to pre-allocate an object that represents "success". Usually one can also pre-allocate objects for the common failure cases. Then only in the rare case of passing back additional detail, is a new object created. (This is the OO equi...
Setting UIButton image results in blue button in iOS 7
...]];
Add an UIImageView to your button.
UIImageView * img = [[UIImageView alloc] initWithImage:[UIImage...]];
[button addSubView:img];
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iPhone: Setting Navigation Bar Title
...ify the last navigation item:
UINavigationItem* item = [[UINavigationItem alloc] initWithTitle:@"title text"];
...
[bar pushNavigationItem:item animated:YES];
[item release];
or
bar.topItem.title = @"title text";
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Changing navigation title programmatically
...vigationItem is also set. Generally, this is better than programmatically allocating and initializing a UINavigationBar that's not linked to anything.
You miss out on some of the benefits and functionality that the UINavigationBar was designed for. Here is a link to the documentation that may help...
How to create a sub array from another array in Java?
...e nulls trailing elements if they are out of source array range instead of allocating a smaller array :(
– Daneel S. Yaitskov
Jun 26 '15 at 14:59
12
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IOS: verify if a point is inside a rect
...is in the UIView instance you are using.
Example:
UIView *aView = [UIView alloc]initWithFrame:CGRectMake(0,0,100,100);
CGPoint aPoint = CGPointMake(5,5);
BOOL isPointInsideView = [aView pointInside:aPoint withEvent:nil];
s...