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C++11 emplace_back on vector?
...
If you do not want to (or cannot) add a constructor, specialize allocator for T (or create your own allocator).
namespace std {
template<>
struct allocator<T> {
typedef T value_type;
value_type* allocate(size_t n) { return static_cast<value_type*>...
Function pointers, Closures, and Lambda
...riables. The compiler created a new closure (not function) dynamically by allocating a new record containing a pointer to the same code, but with different values for the free variables.
You can simulate all this in C, but it is a pain in the ass. Two techniques are popular:
Pass a pointer to ...
boost::flat_map and its performance compared to map and unordered_map
... few variations of the scenario.
A container performance is affected by:
Allocator
size of contained type
cost of implementation of copy operation, assignment operation, move operation, construction operation, of the contained type.
number of elements in the container (size of the problem)
type ha...
How to filter NSFetchedResultsController (CoreData) with UISearchDisplayController/UISearchBar
...llTableCell"];
if (cell == nil)
{
cell = [[[CallTableCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:@"CallTableCell"] autorelease];
}
[self fetchedResultsController:[self fetchedResultsControllerForTableView:theTableView] configureCell:cell atIndexPat...
Why use pointers? [closed]
...ng "char array" to another variable, that only got a certain limited space allocated. You would most likely end up writing over something else in the memory and cause your program to crash (if you are lucky).
Oh, and if you don't assign a string value to the char array / pointer when you declare it...
Is a memory leak created if a MemoryStream in .NET is not closed?
...AK and how much LATER you mean...
If by leak you mean "the memory remains allocated, unavailable for use, even though you're done using it" and by latter you mean anytime after calling dispose, then then yes there may be a leak, although its not permanent (i.e. for the life of your applications run...
What is exactly the base pointer and stack pointer? To what do they point?
... ; Create new frame pointer pointing to current stack top
sub esp, 20 ; allocate 20 bytes worth of locals on stack.
Then later in the function you may have code like (presuming both local variables are 4 bytes)
mov [ebp-4], eax ; Store eax in first local
mov ebx, [ebp - 8] ; Load ebx from ...
Total number of items defined in an enum
...h the Enum.GetValues and Enum.GetNames as listed above seem like they risk allocating a whole new array just to get a fixed length, which seems... well, horrible. Does anyone know if this approach does indeed incur dynamic allocation? If so, for certain use cases it seems far and away the most perfo...
Where in memory are my variables stored in C?
...red in functions), variables (in main function), pointers, and dynamically allocated space (using malloc and calloc) get stored in memory?
...
What is the difference between mutex and critical section?
...n
the critical section structure holds room for a mutex. It is initially unallocated
if there is contention between threads for a critical section, the mutex will be allocated and used. The performance of the critical section will degrade to that of the mutex
if you anticipate high contention, you c...