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How do you clear a slice in Go?
...o reuse the slice (and the underlying array storage) so I'm not constantly allocating a new slice (with array). I've edited my question to clarify and to show some example code from the standard library.
– Chris Weber
Jun 7 '13 at 15:19
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How do I get a background location update every n minutes in my iOS application?
...oken;
dispatch_once(&onceToken, ^{
sharedInstance = [[self alloc] init];
LocationManager *instance = sharedInstance;
instance.locationManager = [CLLocationManager new];
instance.locationManager.delegate = instance;
instance.locationManager.desiredAccur...
C++ valarray vs. vector
...ided to use std::vector while paying close attention to things like memory allocation and temporary object creation.
Both std::vector and std::valarray store the data in a contiguous block. However, they access that data using different patterns, and more importantly, the API for std::valarray e...
Are arrays passed by value or passed by reference in Java? [duplicate]
...itself is passed by value, confused yet?). Quick example:
// assuming you allocated the list
public void addItem(Integer[] list, int item) {
list[1] = item;
}
You will see the changes to the list from the calling code. However you can't change the reference itself, since it's passed by value:...
Most efficient way to create a zero filled JavaScript array?
...second parameter of Array.from.
In the example above, the first parameter allocates an array of 3 positions filled with the value undefined and then the lambda function maps each one of them to the value 0.
Although Array(len).fill(0) is shorter, it doesn't work if you need to fill the array by do...
Design by contract using assertions or exceptions? [closed]
... of recovery can take place. For example, it may be that you're trying to allocate memory. When you catch a 'std::bad_alloc' exception it might be possible to free up memory and try again.
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Why is address zero used for the null pointer?
..., because it means freeing the pointer again isn't dangerous; when I call malloc it returns a pointer with the value zero if it can't get me memory; I use if (p != 0) all the time to make sure passed pointers are valid, etc.
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Dictionary vs Object - which is more efficient and why?
...e, you are incurring additional overhead because of e.g. additional memory allocations and code execution (e.g. of the __init__ method).
In your code, if o is an Obj instance, o.attr is equivalent to o.__dict__['attr'] with a small amount of extra overhead.
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Is there a reason that Swift array assignment is inconsistent (neither a reference nor a deep copy)?
...ds to change the size of a. In particular, it never needs to do any memory allocation. Regardless of the value of i, this is a lightweight operation. If you imagine that under the hood a is a pointer, it can be a constant pointer.
The second line may be much more complicated. Depending on the value...
How to perform Callbacks in Objective-C
...ts delegate, then there would be a retain cycle. It's a good idea in the dealloc method of a class that that has a MyClass instance and is its delegate to clear that delegate reference since it's a weak back pointer. Otherwise if something is keeping the MyClass instance alive, you'll have a danglin...