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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
...
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 can I install pip on Windows?
...
Python 2.7.9+ and 3.4+
Good news! Python 3.4 (released March 2014) and Python 2.7.9 (released December 2014) ship with Pip. This is the best feature of any Python release. It makes the community's wealth of libraries accessible to everyon...
Change default primary key in Eloquent
...d to make sure you set public $incrementing = false otherwise laravel will cast the field to an Integer, giving 0
class User extends Model {
protected $primaryKey = 'my_string_key';
public $incrementing = false;
}
...
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...
How to set enum to null
...
@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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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...
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...