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What is a C++ delegate?
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std::function doesn't always dynamically allocate
– Lightness Races in Orbit
Jul 13 '19 at 14:56
3
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Why should I prefer to use member initialization lists?
...le, but imagine if you will that A's default constructor did more, such as allocating memory or opening files. You wouldn't want to do that unnecessarily.
Furthermore, if a class doesn't have a default constructor, or you have a const member variable, you must use an initializer list:
class A
{
p...
recursion versus iteration
...w the return back to the caller functions. In many cases, memory has to be allocated and copied to implement scope isolation.
Some optimizations, like tail call optimization, make recursions faster but aren't always possible, and aren't implemented in all languages.
The main reasons to use recursi...
Can't use Swift classes inside Objective-C
...}
}
Objective-C code (calling code)
SwiftClass *obj = [[SwiftClass alloc] initWithStringValue: @"Hello World!"];
[obj printValue];
NSString * str = obj.stringValue;
obj.stringValue = @"HeLLo wOrLd!!!";
Result
4. Call Objective-c class from Swift code
Objective-C class (ObjcClass.h)
#impo...
How to avoid overflow in expr. A * B - C * D
... Both long long and double are 64 bits. Since double has to allocate some bits for the exponent, it has a smaller range of possible values without loss of precision.
– Jim Garrison
Nov 5 '12 at 19:03
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iPhone: How to switch tabs with an animation?
...oller:(UIViewController *)toVC
{
return [[TabSwitchAnimationController alloc] init];
}
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Implementing IDisposable correctly
...enting IDisposable, you are announcing that
// instances of this type allocate scarce resources.
public class MyResource: IDisposable
{
// Pointer to an external unmanaged resource.
private IntPtr handle;
// Other managed resource this class uses.
priv...
Why does sizeof(x++) not increment x?
...untime. (Note: Variable Length Arrays are a specific feature -- not arrays allocated with malloc(3).) Otherwise, only the type of the expression is computed, and that at compile time.
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Generate an integer that is not among four billion given ones
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For the 1 GB RAM variant you can use a bit vector. You need to allocate 4 billion bits == 500 MB byte array. For each number you read from the input, set the corresponding bit to '1'. Once you done, iterate over the bits, find the first one that is still '0'. Its index is the answer.
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How to make MySQL handle UTF-8 properly
...taking extra storage when most text is ASCII. Although char strings are preallocated, varchar strings are not -- see the last few lines on this documentation page. For example, char(10) will be pessimistically reserve 40 bytes under utf8mb4, but varchar(10) will allocate bytes in keeping with the v...