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How to alter a column's data type in a PostgreSQL table?
... For some other cases, you might need to specify the way to cast like ALTER TABLE tbl_name ALTER COLUMN col_name TYPE integer USING col_name::integer;
– Nobu
May 1 '14 at 17:45
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Double negation (!!) in javascript - what is the purpose? [duplicate]
...
It casts to boolean. The first ! negates it once, converting values like so:
undefined to true
null to true
+0 to true
-0 to true
'' to true
NaN to true
false to true
All other expressions to false
Then the other ! negates i...
How to set enum to null
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@equiman no need to cast since the type is specified on the left, you are basically duplicating the first part of my answer that is already accepted.
– Rodney S. Foley
Jul 8 '15 at 22:50
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How to know user has clicked “X” or the “Close” button?
...er X or your CloseButton, you may get it through the sender object. Try to cast sender as a Button control, and verify perhaps for its name "CloseButton", for instance.
private void Form1_FormClosing(object sender, FormClosingEventArgs e) {
if (string.Equals((sender as Button).Name, @"CloseButt...
capturing self strongly in this block is likely to lead to a retain cycle
...ple of members of self in this block, most likely just to update a slider. Casting self is overkill. Instead, it's better to be explicit and cast only the objects that you truly need inside the block. For example, if it's an instance of UISlider*, say, _timeSlider, just do the following before the b...
RESTful Authentication via Spring
...(user/pass combo) with each request is not desirable. Per REST guidelines (and internal business requirements), the server must remain stateless. The API will be consumed by another server in a mashup-style approach.
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How to convert IEnumerable to ObservableCollection?
...ble original)
{
return new ObservableCollection<object>(original.Cast<object>());
}
If you're working with generic IEnumerable<T> you can do it this way:
public ObservableCollection<T> Convert<T>(IEnumerable<T> original)
{
return new ObservableCollection...
How do you implement a class in C? [closed]
...s the proper class, i.e. RectangleClass *. This means you often have to do casts, but they provide handy macros do help with that, so you can always cast BASECLASS *p to SUBCLASS * using just SUBCLASS(p).
– unwind
Sep 10 '09 at 8:03
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How different is Objective-C from C++? [closed]
...Objective-C is a more perfect superset of C. In C and Objective-C implicit casting from void* to a struct pointer is allowed.
Foo* bar = malloc(sizeof(Foo));
C++ will not compile unless the void pointer is explicitly cast:
Foo* bar = (Foo*)malloc(sizeof(Foo));
The relevance of this to every da...
Which one will execute faster, if (flag==0) or if (0==flag)?
...caveat: Nawaz did point out the user-defined trap. And I regret my hastily cast upvote on "stupidest question" because it seems that many did not get it right and it gives room for a nice discussion on compiler optimization :)
The answer is:
What is flag's type?
In the case where flag actuall...