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How do you copy the contents of an array to a std::vector in C++ without looping?
...ce() first on the two iterators to get the needed number of elements, then allocate just once.
– Drew Hall
Nov 4 '08 at 2:38
4
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iOS difference between isKindOfClass and isMemberOfClass
...se
@interface A : NSObject
@end
@interface B : A
@end
...
id b = [[B alloc] init];
then
[b isKindOfClass:[A class]] == YES;
[b isMemberOfClass:[A class]] == NO;
Basically, -isMemberOfClass: is true if the instance is exactly of the specified class, while -isKindOfClass: is true if the ins...
What is the difference between exit and return? [duplicate]
...ogram after the processus stopped, hence it wouldn't make much difference: allocated memory will be freed, file ressource closed and so on. But it may matter if your destructor performs IOs. For instance automatic C++ OStream locally created won't be flushed on a call to exit and you may lose some u...
How to find a min/max with Ruby
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Punctuation isn't the problem here. An entire heap allocation to get the max of a few values is the underlying ugliness here.
– kdbanman
Mar 7 '15 at 21:37
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UITableView load more when scrolling to bottom like Facebook application
...thIdentifier:cellIdentifier];
if (!cell)
{
cell = [[MyCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:MainMenuCellIdentifier];
}
MyData *data = [self.dataArray objectAtIndex:indexPath.row];
// Do your cell customisation
// cell.titleLabel.text =...
Why does changing 0.1f to 0 slow down performance by 10x?
... credits to Carl Hetherington [1])
[1] http://carlh.net/plugins/denormals.php
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Check for column name in a SqlDataReader object
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You're enumerating the field names multiple times / allocating another array to scan with a contains, this would be much less performant in high traffic code.
– Chad Grant
Oct 4 '19 at 17:44
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Find size of object instance in bytes in c#
...t one thing to keep in mind with garbage collected/managed runtimes is the allocated size of an object can change throughout the lifetime of the program. For example, some generational garbage collectors (such as the Generational/Ulterior Reference Counting Hybrid collector) only need to store certa...
Default value of BOOL
...nce variables of Objective-C objects are always set to 0 (or nil) when you allocate an object" and I cannot find any other, clearer, reference, so it's all a bit contradictory to me.
– Kristof Van Landschoot
Sep 9 '13 at 8:47
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What is a handle in C++?
... the result of a new expression is a "normal" pointer. A managed object is allocated on the GC (managed) heap with a gcnew expression. The result will be a handle. You can't do pointer arithmetic on handles. You don't free handles. The GC will take care of them. Also, the GC is free to relocate obje...