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Objective-C class -> string like: [NSArray className] -> @“NSArray”

... Class arrayClass = NSClassFromString (name); id anInstance = [[arrayClass alloc] init]; share | improve this answer | follow | ...
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When should I use a struct instead of a class?

...hort-living. In such a case there is a good chance that the object will be allocated on the stack which is much more efficient than putting it on the managed heap. What is more the memory allocated by the object will be freed as soon as it goes outside its scope. In other words it's less work for Ga...
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Java8 Lambdas vs Anonymous classes

...st don't try to use your counter from multiple threads. If you're going to allocate something on the heap and capture it in a lambda, you might as well use an AIC and add a field that you can mutate directly. Using a lambda this way can work, but why bother when you can use a real object? ...
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Make first letter of a string upper case (with maximum performance)

...lternative char.ToUpper(s[0]) + s.Substring(1), is that only one string is allocated, whereas the Substring approach allocates a string for the substring, then a second string to compose the final result. EDIT: Here is what this approach looks like, combined with the initial test from CarlosMuño...
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Convert NSData to String?

...oding:(NSStringEncoding)encoding Example: NSString *myString = [[NSString alloc] initWithData:myData encoding:NSUTF8StringEncoding]; Remark: Please notice the NSData value must be valid for the encoding specified (UTF-8 in the example above), otherwise nil will be returned: Returns nil if the ini...
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How do I call ::std::make_shared on a class with only protected or private constructors?

... suitable to hold an object of type T, shall be well formed. A shall be an allocator (17.6.3.5). The copy constructor and destructor of A shall not throw exceptions. Since the requirement is unconditionally specified in terms of that expression and things like scope aren't taken into account, I th...
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CSS background-image - What is the correct usage?

... must be escaped with a backslash so that the resulting URI value is a URI token: '\(', '\)'. So in instances such as these it is either necessary to use quotes or double quotes, or escape the characters. share | ...
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Custom Cell Row Height setting in storyboard is not responding

...ormance penalty as said @Brennan in comments, it also cause growing memory allocation at each reloadData something like memory leak! It's needed to use lensovet's workaround above! Spend a day to catch this memory leak! – skywinder May 28 '14 at 15:35 ...
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How can I use NSError in my iPhone App?

...error:(NSError **)error { FSProfileInfo *profileInfo = [[FSProfileInfo alloc] init]; if (profileInfo) { /* ... lots of parsing code here ... */ if (profileInfo.username == nil) { *error = [NSError errorWithDomain:FSMyAppErrorDomain code:FSProfileParsi...
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warning about too many open figures

... in a Jupyter environment, does the memory allocation persist as long as the cell showing the plot exists? – matanster Aug 26 '18 at 15:34 3 ...