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Why are function pointers and data pointers incompatible in C/C++?
...be converted back to the original function pointer type, using an explicit cast, without loss of information. Note: The ISO C standard does not require this, but it is required for POSIX conformance.
– Jonathan Leffler
Sep 11 '12 at 18:23
...
Safe (bounds-checked) array lookup in Swift, through optional bindings?
..., to clarify the situation: b contains a value and the value is nil. If we casted automatically to Int?, we would loose the information, if we got a hit or a miss in the array, which might be necessary in some circumstances. I would rather debate, if Swift could get rid of automatically casting valu...
Receive result from DialogFragment
...t will not working after save and restore dialog fragment state. LocalBroadcastManager is best solution in this case.
– Nik
Aug 10 '16 at 12:50
4
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Using the Swift if let with logical AND operator &&
...n("do stuff")
}
This uses the where clause.
Another example, this time casting AnyObject to Int, unwrapping the optional, and checking that the unwrapped optional meets the condition:
if let w = width as? Int where w < 500
{
println("success!")
}
For those now using Swift 3, "where" ha...
Why doesn't Java offer operator overloading?
...and one double. There is even the whole pointer arithmetic domain (without casting, you can add to a pointer an integer, but you cannot add two pointers...).
In Java, there is no pointer arithmetic, but someone still found string concatenation without the + operator would be ridiculous enough to ju...
Cannot set some HTTP headers when using System.Net.WebRequest
...cause of multiple ways to do this. When using WebRequest.Create() you can cast to an HttpWebRequest and use the property to add or modify a header. When using a WebHeaderCollection you may use the .Add("referer","my_url").
Ex 1
WebClient client = new WebClient();
client.Headers.Add("referer", "ht...
Why is there no multiple inheritance in Java, but implementing multiple interfaces is allowed?
...
@curiousguy: If a framework provides that casting an object reference to a base-type reference will be identity preserving, then every object instance must have exactly one implementation of any base-class method. If ToyotaCar and HybridCar both derived from Car and...
Using bitwise OR 0 to floor a number
...
How does it work? Our theory was that using such an operator casts the
number to an integer, thus removing the fractional part
All bitwise operations except unsigned right shift, >>>, work on signed 32-bit integers. So using bitwise operations will convert a float to an in...
MIN and MAX in C
... macro from doing such potentially dangerous type promotions, a final type cast to the intended type was used.
Rationale
We want both parameters to the macro to be of the same type. If one of them is of a different type, the macro is no longer type safe, because an operator like ?: will yield impl...
What is the difference between string primitives and String objects in JavaScript?
...(s).prototype.toString.call = [object String].
The auto-boxing behaviour casts s back and forth to its wrapper type as needed, but the standard operations are incredibly fast since you are dealing with a simpler data type. However auto-boxing and Object.prototype.valueOf have different effects.
I...