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Comparing two collections for equality irrespective of the order of items in them
...g answers, since it takes nulls into account, implements IEqualityComparer and has some efficiency and edge case checks. plus, it's Microsoft :)
public class MultiSetComparer<T> : IEqualityComparer<IEnumerable<T>>
{
private readonly IEqualityComparer<T> m_comparer;
p...
Programmatic equivalent of default(Type)
I'm using reflection to loop through a Type 's properties and set certain types to their default. Now, I could do a switch on the type and set the default(Type) explicitly, but I'd rather do it in one line. Is there a programmatic equivalent of default?
...
Why must a lambda expression be cast when supplied as a plain Delegate parameter
... new delegate type with an appropriate signature, but that's rarely useful and you end up with less opportunity for error checking.
If you want to make it easy to call Control.Invoke with an Action the easiest thing to do is add an extension method to Control:
public static void Invoke(this Contro...
Help with C# generics error - “The type 'T' must be a non-nullable value type”
I'm new to C# and don't understand why the following code doesn't work.
4 Answers
4
...
initializer_list and move semantics
...ist existed to keep an array of temporaries until they were move'd.
begin and end for initializer_list return const T *, so the result of move in your code is T const && — an immutable rvalue reference. Such an expression can't meaningfully be moved from. It will bind to an function param...
Python: How to get stdout after running os.system? [duplicate]
...t
Or as a function (using shell=True was required for me on Python 2.6.7 and check_output was not added until 2.7, making it unusable here):
def system_call(command):
p = subprocess.Popen([command], stdout=subprocess.PIPE, shell=True)
return p.stdout.read()
...
When to use IList and when to use List
I know that IList is the interface and List is the concrete type but I still don't know when to use each one. What I'm doing now is if I don't need the Sort or FindAll methods I use the interface. Am I right? Is there a better way to decide when to use the interface or the concrete type?
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Java: Instanceof and Generics
...Object(Class<T> type) {
return new MyObject<T>(type);
}
And then in the object's constructor store that type, so variable so that your method could look like this:
if (arg0 != null && !(this.type.isAssignableFrom(arg0.getClass()))
{
return -1;
...
What is the difference between SQL, PL-SQL and T-SQL?
What is the difference between SQL, PL-SQL and T-SQL?
6 Answers
6
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php is null or empty?
...===.
When use ==, as you did, PHP treats NULL, false, 0, the empty string, and empty arrays as equal.
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