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How to detect if a property exists on an ExpandoObject?
...efined" to a special object's const value i created elsewhere. It prevents casting problems :p
– Softlion
Dec 15 '10 at 6:02
1
...
When do you use the “this” keyword? [closed]
...e (struct) value.
To invoke an extension method on the current instance
To cast itself to another type
To chain constructors defined in the same class
You can avoid the first usage by not having member and local variables with the same name in scope, for example by following common naming conventi...
What's the correct way to communicate between controllers in AngularJS?
...essed in this answer have been resolved in angular.js version 1.2.7. $broadcast now avoids bubbling over unregistered scopes and runs just as fast as $emit.
So, now you can:
use $broadcast from the $rootScope
listen using $on from the local $scope that needs to know about the event
Original ...
Create Generic method constraining T to an Enum
...ty else str
Enum.GetValues(typedefof<'T>)
|> Seq.cast<_>
|> Seq.tryFind(fun v -> String.Compare(v.ToString(), str.Trim(), true) = 0)
|> function Some x -> x | None -> defaultValue
This one is easier to maintain since it's a well-known l...
What is array to pointer decay?
...
const int a[] = { 2, 3, 5, 7, 11 };
into a pointer (which works without casting, and therefore can happen unexpectedly in some cases):
const int* p = a;
you lose the ability of the sizeof operator to count elements in the array:
assert( sizeof(p) != sizeof(a) ); // sizes are not equal
This...
Implicit type conversion rules in C++ operators
I want to be better about knowing when I should cast. What are the implicit type conversion rules in C++ when adding, multiplying, etc. For example,
...
Why do std::shared_ptr work
...late <typename T>
void delete_deleter( void * p ) {
delete static_cast<T*>(p);
}
template <typename T>
class my_unique_ptr {
std::function< void (void*) > deleter;
T * p;
template <typename U>
my_unique_ptr( U * p, std::function< void(void*) > deleter ...
When should I use cross apply over inner join?
...N
(
SELECT TOP 2 ID, PERIOD,QTY
FROM DETAILS D
ORDER BY CAST(PERIOD AS DATE)DESC
)D
ON M.ID=D.ID
SQL FIDDLE
The above query generates the following result.
x------x---------x--------------x-------x
| Id | Name | PERIOD | QTY |
x------x---------x--------------x--...
How to implement the factory method pattern in C++ correctly
...f.registerType<Descendant2>("Descendant2");
Descendant1* d1 = static_cast<Descendant1*>(f.create("Descendant1"));
Descendant2* d2 = static_cast<Descendant2*>(f.create("Descendant2"));
BaseClass *b1 = f.create("Descendant1");
BaseClass *b2 = f.create("Descendant2");
...
How to use Class in Java?
...is overriding the T declared at Class level;
//So There is no ClassCastException though a is not the type of T declared at MyClass<T>.
private <T> T myMethod1(Object a){
return (T) a;
}
//Runtime ClassCastException will be thrown if a is ...