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In Objective-C why should I check if self = [super init] is not nil?
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For example:
[[NSData alloc] initWithContentsOfFile:@"this/path/doesn't/exist/"];
[[NSImage alloc] initWithContentsOfFile:@"unsupportedFormat.sjt"];
[NSImage imageNamed:@"AnImageThatIsntInTheImageCache"];
... and so on. (Note: NSData might throw...
What is your favorite C programming trick? [closed]
...you should be aware there are some issues with this for large, dynamically allocated structures.
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edited May 23 '17 at 11:54
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How is std::function implemented?
... dynamically. The std::function object is always of the same size and will allocate space as needed for the different functors in the heap.
In real life there are different optimizations that provide performance advantages but would complicate the answer. The type could use small object optimizatio...
How to make completely transparent navigation bar in iOS 7
...or];
[self.navigationController.navigationBar setBackgroundImage:[[UIImage alloc] init] forBarMetrics:UIBarMetricsDefault];
self.navigationController.navigationBar.shadowImage = [[UIImage alloc] init];
self.navigationController.navigationBar.backgroundColor = [UIColor clearColor];
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Adding a simple UIAlertView
...u want the alert to show, do this:
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"ROFL"
message:@"Dee dee doo doo."
delegate:self
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Python List vs. Array - when to use?
...discontiguous and sparse arrays, and I think some pluggable strategies for allocating memory for large arrays... some of these advanced features will make it user less memory, while others will improve performance by using more memory.
– Dan Lenski
Oct 29 '14 a...
Best Practice for Forcing Garbage Collection in C#
...ram idles, the memory in use is not garbage-collected because there are no allocations.
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Why does struct alignment depend on whether a field type is primitive or user-defined?
...e conscious decision.
EDIT
The sizes are actually accurate only when allocated on a heap but the structs themselves have smaller sizes (the exact sizes of it's fields). Further analysis seam to suggest that this might be a bug in the CLR code, but needs to be backed up by evidence.
I will in...
In what cases do I use malloc and/or new?
I see in C++ there are multiple ways to allocate and free data and I understand that when you call malloc you should call free and when you use the new operator you should pair with delete and it is a mistake to mix the two (e.g. Calling free() on something that was created with the new ...
What is a smart pointer and when should I use one?
...nt: When a smart pointer is no longer in use, the memory it points to is deallocated (see also the more detailed definition on Wikipedia).
When should I use one?
In code which involves tracking the ownership of a piece of memory, allocating or de-allocating; the smart pointer often saves you the ne...