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What is the “Execute Around” idiom?

...e you write a method to do things which are always required, e.g. resource allocation and clean-up, and make the caller pass in "what we want to do with the resource". For example: public interface InputStreamAction { void useStream(InputStream stream) throws IOException; } // Somewhere else ...
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Explain the concept of a stack frame in a nutshell

...rocessor knows anything about stack, because WE manipulate it via subbing (allocation), pushing and popping. And so here are calling conventions which explain how we should use the stack. – Victor Polevoy Apr 18 '18 at 7:18 ...
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What does the “__block” keyword mean?

...and static.[testme] Variables qualified by __block act as if they were in allocated storage and this storage is automatically recovered after last use of said variable. An implementation may choose an optimization where the storage is initially automatic and only "moved" to allocated (heap) storag...
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Why was “Avoid Enums Where You Only Need Ints” removed from Android's performance tips?

... TLDR: Dalvik was not good with memory allocation and Enum uses more memory than int. Android Lollipop replaced Dalvik with ART which does not suffer from the same limitations. Thus this recommendation is not relevant anymore. The long answer: Wow! 8 years, 5 a...
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Determine the number of lines within a text file

...ne loads the entire contents of the file into an array which means it must allocate at least as much memory as the size of the file. The second merely loops one line at a time so it never has to allocate more than one line's worth of memory at a time. This isn't that important for small files, but f...
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What do the plus and minus signs mean in Objective-C next to a method?

...se? [CustomClass classMethod]; CustomClass *classObject = [[CustomClass alloc] init]; [classObject instanceMethod]; share | improve this answer | follow | ...
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How do I concatenate two strings in C?

....h> char* concat(const char *s1, const char *s2) { char *result = malloc(strlen(s1) + strlen(s2) + 1); // +1 for the null-terminator // in real code you would check for errors in malloc here strcpy(result, s1); strcat(result, s2); return result; } This is not the fastest wa...
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Array versus linked-list

... @Rick, vectors typically overallocate the space they require so that they don't need to allocate new space everytime the size increases. The result is that vectors are typically much less memory intensive, not more then linked lists. ...
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Quickly create large file on a Windows system

...oftware/rdfc/index-en.html RDFC is probably not the fastest, but it does allocate data blocks. The absolutely fastest would have to use lower level API to just obtain cluster chains and put them into MFT without writing data. Beware that there's no silver bullet here - if "creation" returns insta...
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Programmatically add custom event in the iPhone Calendar

... { [super viewDidLoad]; EKEventStore *eventStore = [[EKEventStore alloc] init]; EKEvent *event = [EKEvent eventWithEventStore:eventStore]; event.title = @"EVENT TITLE"; event.startDate = [[NSDate alloc] init]; event.endDate = [[NSDate alloc] initWithTimeInterval:600...