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String length in bytes in JavaScript
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If you only need the length, it might be overkill to allocate a new string, do the actual conversion, take the length, and then discard the string. See my answer above for a function that just computes the length in an efficient manner.
– lovasoa
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Create singleton using GCD's dispatch_once in Objective-C
...ace MySingleton : NSObject
+(instancetype)sharedInstance;
+(instancetype)alloc __attribute__((unavailable("alloc not available, call sharedInstance instead")));
-(instancetype)init __attribute__((unavailable("init not available, call sharedInstance instead")));
+(instancetype)new __attribute__((un...
Do threads have a distinct heap?
... a stack overflow.
Since all threads share the same heap, access to the allocator/deallocator must be synchronized. There are various methods and libraries for avoiding allocator contention.
Some languages allow you to create private pools of memory, or individual heaps, which you can assign ...
Segmentation fault on large array sizes
...The array is too big to fit in your program's stack address space.
If you allocate the array on the heap you should be fine, assuming your machine has enough memory.
int* array = new int[1000000];
But remember that this will require you to delete[] the array. A better solution would be to use st...
Difference between 'new operator' and 'operator new'?
...er, but it's a good question in any case.
Operator new is a function that allocates raw memory -- at least conceptually, it's not much different from malloc(). Though it's fairly unusual unless you're writing something like your own container, you can call operator new directly, like:
char *x = st...
Is there a max array length limit in C++?
...d char[].
Additionally, this upper limit may be influenced by the type of allocator used to construct the vector because an allocator is free to manage memory any way it wants. A very odd but nontheless conceivable allocator could pool memory in such a way that identical instances of an object shar...
Xcode without Storyboard and ARC
...gWithOptions: (NSDictionary *)launchOptions
{
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
// Override point for customization after application launch.
TestViewController *test = [[TestViewController alloc] initWithNibName:@"TestViewController" bundle...
Is it possible to get all arguments of a function as single object inside that function?
...uments); cant be the best way because it causes an unnecessary empty array allocation.
– Thomas Eding
Jun 22 '17 at 16:49
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How do I set bold and italic on UILabel of iPhone/iPad?
... Using the font descriptor you need no names:
UILabel * label = [[UILabel alloc] init]; // use your label object instead of this
UIFontDescriptor * fontD = [label.font.fontDescriptor
fontDescriptorWithSymbolicTraits:UIFontDescriptorTraitBold
| UIFontDescripto...
How do I declare a 2d array in C++ using new?
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Remember that anything allocated with new is created on the heap and must be de-allocated with delete, just keep this in mind and be sure to delete this memory from the heap when you're done with it to prevent leaks.
– Kekoa
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