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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
...
Why would finding a type's initializer throw a NullReferenceException?
...found at least 3 workaround approaches for fixing the problem:
Simply by casting the Type to _Type inside the Main method:
var cctor = ((_Type)typeof(Test)).TypeInitializer;
Or making sure that approach 1 was used previously inside the method:
var warmUp = ((_Type)typeof(Test)).TypeInitializer;...
How do you create a dropdownlist from an enum in ASP.NET MVC?
...adata);
IEnumerable<TEnum> values = Enum.GetValues(enumType).Cast<TEnum>();
IEnumerable<SelectListItem> items = from value in values
select new SelectListItem
{
Text = GetEnumDescription(value),
Value = value....
What is an example of the Liskov Substitution Principle?
...
A great example illustrating LSP (given by Uncle Bob in a podcast I heard recently) was how sometimes something that sounds right in natural language doesn't quite work in code.
In mathematics, a Square is a Rectangle. Indeed it is a specialization of a rectangle. The "is a" makes you...
vs in Generics
...of the generic class, interface or method. The implication is that you can cast the type/interface/method to an equivalent with a super-type of T.
E.g. ICovariant<out Dog> can be cast to ICovariant<Animal>.
share...
Adding two Java 8 streams, or an extra element to a stream
...type of Something<? extends T>, not the other way, so it couldn't be cast) Additional .map(identity()) cast <? extends T> to <T>. It happens thanks to mix of java 8 'target types' of method arguments and return types and signature of map() method. Actually it is Function.<T>i...
Measuring execution time of a function in C++
...::high_resolution_clock::now();
auto duration = std::chrono::duration_cast<std::chrono::microseconds>( t2 - t1 ).count();
std::cout << duration;
return 0;
}
This will measure the duration of the function.
NOTE: You will not always get the same timing for a function. This...
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...
T-SQL datetime rounded to nearest minute and nearest hours with using functions
...en the datetime in question and a fixed point in time (0, which implicitly casts to 1900-01-01 00:00:00.000):
declare @days int
set @days = datediff(day, 0, @dt)
and then add that number of days to the fixed point in time, which gives you the original date with the time set to 00:00:00.000:
sele...
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...