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C# Lazy Loaded Automatic Properties
... 4.0 Lazy<T> type to create this pattern
private Lazy<string> _someVariable =new Lazy<string>(SomeClass.IOnlyWantToCallYouOnce);
public string SomeVariable => _someVariable.Value;
This code will lazily calculate the value of _someVariable the first time the Value expression i...
What does the “__block” keyword mean?
What exactly does the __block keyword in Objective-C mean? I know it allows you to modify variables within blocks, but I'd like to know...
...
How to get the first column of a pandas DataFrame as a Series?
...c wasn't there yet back then. In 2016, the correct answer is Jeff's (after all he's pandas God, mind you ;-)). I'm not sure what's SO's policy regarding update of answers due to API change; I'm honestly surprised by the number of votes for this answer, didn't think it was that useful to people...
...
Match multiple cases classes in scala
... matcher(l: Foo): String = {
l match {
case A() => "A"
case B(_) | C(_) => "B"
case _ => "default"
}
}
If you must, must, must extract the parameter and treat them in the same code block, you could:
def matcher(l: Foo): String = {
l match {
case A() => "A"
ca...
Dynamic instantiation from string name of a class in dynamically imported module?
...
You can use getattr
getattr(module, class_name)
to access the class. More complete code:
module = __import__(module_name)
class_ = getattr(module, class_name)
instance = class_()
As mentioned below, we may use importlib
import importlib
module = importlib.imp...
Do declared properties require a corresponding instance variable?
...
In your interface, you can formally declare an instance variable between the braces, or via @property outside the braces, or both. Either way, they become attributes of the class. The difference is that if you declare @property, then you can implement usin...
How to dynamic new Anonymous Class?
...
All you're doing is saying that dynamic properties are not identical to strongly-typed properties. This is trivially true.
– Steven Sudit
Sep 18 '10 at 2:31
...
How do I write the 'cd' command in a makefile?
...
It is actually executing the command, changing the directory to some_directory, however, this is performed in a sub-process shell, and affects neither make nor the shell you're working from.
If you're looking to perform more tasks wit...
Cross-Domain Cookies
...erver side you need to have the following headers:
header("Access-Control-Allow-Origin: http://origin.domain:port");
header("Access-Control-Allow-Credentials: true");
header("Access-Control-Allow-Methods: GET, POST");
header("Access-Control-Allow-Headers: Content-Type, *");
Within the PHP-file yo...
Detect iPad users using jQuery?
... to detect an iPad user by taking a look at the userAgent property:
var is_iPad = navigator.userAgent.match(/iPad/i) != null;
iPhone/iPod Detection
Similarly, the platform property to check for devices like iPhones or iPods:
function is_iPhone_or_iPod(){
return navigator.platform.match(/i(...