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Weak and strong property setter attributes in Objective-C
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You either have ARC on or off for a particular file. If its on you cannot use retain release autorelease etc... Instead you use strong weak for properties or __strong
__weak
for variables (defaults to __strong). Strong is the equivalent to retain, however ARC will manage the release for y...
How can I generate a diff for a single file between two branches in github
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Hi,it looks like this won't work for me because my diff is too big. I'm getting "This diff is big! We're showing status information only for the first 2,500 files." so I only get the Diff Stats and not the full diffs, even with the #diff links.
–...
What happens if you static_cast invalid value to enum class?
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Answering with a quote from the C++11 and C++14 Standards:
[expr.static.cast]/10
A value of integral or enumeration type can be explicitly converted to an enumeration type. The value is unchanged if the original value is within the range of the enumeration values (7.2). Otherwise, the resulti...
I want to get the type of a variable at runtime
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So, strictly speaking, the "type of a variable" is always present, and can be passed around as a type parameter. For example:
val x = 5
def f[T](v: T) = v
f(x) // T is Int, the type of x
But depending on what you want to do, that won't help you. For instance, may want not to know what is the ...
How to specify maven's distributionManagement organisation wide?
...figure out how to organize many (around 50+) maven2 projects, so that they can deploy into a central nexus repository. When using the mvn deploy goal, one does need to specify the target in the distributionManagement tag like this:
...
What are the details of “Objective-C Literals” mentioned in the Xcode 4.4 release notes?
...ective-c-literals-for-nsdictionary-nsarray-and:
Objective-C literals: one can now create literals for NSArray, NSDictionary, and NSNumber (just like one can create literals for NSString)
NSArray Literals
Previously:
array = [NSArray arrayWithObjects:a, b, c, nil];
Now:
array = @[ a, b, c ];
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Difference between this and self in JavaScript
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Unless set elsewhere, the value of self is window because JavaScript lets you access any property x of window as simply x, instead of window.x. Therefore, self is really window.self, which is different to this.
window.self === window; // true
If you're using a function that...
Is unsigned integer subtraction defined behavior?
...pe is well-defined:
[...] A computation involving unsigned operands can never overflow,
because a result that cannot be represented by the resulting unsigned integer type is
reduced modulo the number that is one greater than the largest value that can be
represented by the resulting typ...
John Carmack's Unusual Fast Inverse Square Root (Quake III)
John Carmack has a special function in the Quake III source code which calculates the inverse square root of a float, 4x faster than regular (float)(1.0/sqrt(x)) , including a strange 0x5f3759df constant. See the code below. Can someone explain line by line what exactly is going on here and why t...
What guarantees are there on the run-time complexity (Big-O) of LINQ methods?
...(1).
OrderBy methods use a stable quicksort, so they're O(N log N) average case.
I think that covers most if not all of the built-in extension methods. There really are very few performance guarantees; Linq itself will try to take advantage of efficient data structures but it isn't a free pass to...